1377:
2719:
2708:
1391:
1068:
2730:
36:
1271:
EAI enables users to have a localized address in a native language script or character set, as well as an ASCII form for communicating with legacy systems or for script-independent use. Applications that recognize internationalized domain names and mail addresses must have facilities to convert these
1169:
Formal and informal standards: RFC 3696 provides specific advice for validating
Internet identifiers, including email addresses. Some websites instead attempt to evaluate the validity of email addresses through arbitrary standards, such as by rejecting addresses containing valid characters, such as
1196:
Sender reputation: An email sender's reputation may be used to attempt to verify whether the sender is trustworthy or a potential spammer. Factors that may be incorporated into an assessment of sender reputation include the quality of past contact with or content provided by, and engagement levels
1165:
Verification links: Email address validation is often accomplished for account creation on websites by sending an email to the user-provided email address with a special temporary hyperlink. On receipt, the user opens the link, immediately activating the account. Email addresses are also useful as
529:
A local-part is either a Dot-string or a Quoted-string; it cannot be a combination. Quoted strings and characters, however, are not commonly used. RFC 5321 also warns that "a host that expects to receive mail SHOULD avoid defining mailboxes where the Local-part requires (or uses) the Quoted-string
471:
If quoted, it may contain Space, Horizontal Tab (HT), any ASCII graphic except
Backslash and Quote and a quoted-pair consisting of a Backslash followed by HT, Space or any ASCII graphic; it may also be split between lines anywhere that HT or Space appears. In contrast to unquoted local-parts, the
312:
The local-part of an email address has no significance for intermediate mail relay systems other than the final mailbox host. Email senders and intermediate relay systems must not assume it to be case-insensitive, since the final mailbox host may or may not treat it as such. A single mailbox may
1263:
The basic EAI concepts involve exchanging mail in UTF-8. Though the original proposal included a downgrading mechanism for legacy systems, this has now been dropped. The local servers are responsible for the local-part of the address, whereas the domain would be restricted by the rules of
595:
Some mail services support a tag included in the local-part, such that the address is an alias to a prefix of the local-part. Typically the characters following a plus and less often the characters following a minus, so fred+bah@domain and fred+foo@domain might end up in the same inbox as
218:
An email address consists of two parts, a local-part (sometimes a user name, but not always) and a domain; if the domain is a domain name rather than an IP address then the SMTP client uses the domain name to look up the mail exchange IP address. The general format of an email address is
572:"the local-part MUST be interpreted and assigned semantics only by the host specified in the domain of the address". This means that no assumptions can be made about the meaning of the local-part of another mail server. It is entirely up to the configuration of the mail server.
332:
The addresses found in the header fields of an email message are not directly used by mail exchanges to deliver the message. An email message also contains a message envelope that contains the information for mail routing. While envelope and header addresses may be equal,
545:
specify different mailboxes; however, many organizations treat uppercase and lowercase letters as equivalent. Indeed, RFC 5321 warns that "a host that expects to receive mail SHOULD avoid defining mailboxes where ... the Local-part is case-sensitive".
369:
may have a maximum of 255 octets. The formal definitions are in RFC 5322 (sections 3.2.3 and 3.4.1) and RFC 5321—with a more readable form given in the informational RFC 3696 (written by J. Klensin, the author of RFC 5321) and the associated errata.
1247:
The IETF's EAI Working group published RFC 6530 "Overview and
Framework for Internationalized Email", which enabled non-ASCII characters to be used in both the local-parts and domain of an email address. RFC 6530 provides for email based on the
828:
specifies that certain domains, for example those intended for documentation and testing, should not be resolvable and that as a result mail addressed to mailboxes in them and their subdomains should be non-deliverable. Of note for e-mail are
1178:, or enforcing arbitrary length limitations. Email address internationalization provides for a much larger range of characters than many current validation algorithms allow, such as all Unicode characters above U+0080, encoded as
397:
notation, in which the address was given in the form of a sequence of computers through which the message should be relayed. This was widely used for several years, but was superseded by the
Internet standards promulgated by the
170:
enclosed in brackets. Although the standard requires the local-part to be case-sensitive, it also urges that receiving hosts deliver messages in a case-independent manner, e.g., that the mail system in the domain
495:
are allowed with restrictions (they are only allowed inside a quoted string, as described in the paragraph below, and in that quoted string, any backslash or double-quote must be preceded once by a backslash);
2093:
93:
box to which messages are delivered. While early messaging systems used a variety of formats for addressing, today, email addresses follow a set of specific rules originally standardized by the
1296:
now supplies a free email account on domain राजस्थान.भारत for every citizen of the state. A leading media house
Rajasthan Patrika launched their IDN domain पत्रिका.भारत with contactable email.
549:
Despite the wide range of special characters which are technically valid, organisations, mail services, mail servers and mail clients in practice often do not accept all of them. For example,
373:
An email address also may have an associated "display-name" (Display Name) for the recipient, which precedes the address specification, now surrounded by angled brackets, for example:
377:. Email spammers and phishers will often use "Display Name spoofing" to trick their victims, by using a false Display Name, or by using a different email address as the Display Name.
231:. The SMTP client transmits the message to the mail exchange, which may forward it to another mail exchange until it eventually arrives at the host of the recipient's mail system.
313:
receive mail for multiple email addresses, if configured by the administrator. Conversely, a single email address may be the alias to a distribution list to many mailboxes.
1292:
for use by
Gujrati, Marathi, Bangali, Tamil, Telugu, Punjabi and Urdu speakers. Indian company XgenPlus.com claims to be the world's first EAI mailbox provider, and the
537:
is treated specially—it is case-insensitive, and should be forwarded to the domain email administrator. Technically all other local-parts are case-sensitive, therefore
1120:
Email addresses are often requested as input to website as validation of user existence. Other validation methods are available, such as cell phone number validation,
1991:
2299:
2085:
1546:
1275:
Significant demand for such addresses is expected in China, Japan, Russia, and other markets that have large user bases in a non-Latin-based writing system.
2431:
329:
addresses, the latter being mailboxes that receive messages regardless of the local-part, are common patterns for achieving a variety of delivery goals.
2511:
1819:
54:
2473:
349:, and many other Internet-based scams. This has led to several initiatives which aim to make such forgeries of fraudulent emails easier to spot.
1268:, though still transmitted in UTF-8. The mail server is also responsible for any mapping mechanism between the IMA form and any ASCII alias.
2711:
1532:"...you can add or remove the dots from a mail address without changing the actual destination address; and they'll all go to your inbox..."
579:
may distinguish mailboxes differing only in capitalization of characters of the local-part, although this is not very common. For example,
519:
1185:
Algorithmic tools: Large websites, bulk mailers and spammers require efficient tools to validate email addresses. Such tools depend upon
2122:
799:) allow for presentation of non-ASCII domains. In mail systems compliant with RFC 6531 and RFC 6532 an email address may be encoded as
631:
Addresses of this form, using various separators between the base name and the tag, are supported by several email services, including
1902:
2064:
278:
187:. Mail systems often limit the users' choice of name to a subset of the technically permitted characters; with the introduction of
1200:
Browser-based verification: HTML5 forms implemented in many browsers allow email address validation to be handled by the browser.
2243:
526:, though even mail systems that support SMTPUTF8 and 8BITMIME may restrict which characters to use when assigning local-parts.
2352:
575:
Interpretation of the local-part is dependent on the conventions and policies implemented in the mail server. For example,
2324:
1142:
exists. Thus many mail servers use other techniques and check the mailbox existence against relevant systems such as the
1999:
920:
2173:
523:
2696:
Update to
Internet Message Format to Allow Group Syntax in the "From:" and "Sender:" Header Fields (Updates RFC 5322)
1220:
conducts a technical and standards working group devoted to internationalization issues of email addresses, entitled
1205:
1107:
463:, provided that it is not the first or last character and provided also that it does not appear consecutively (e.g.,
202:
by many websites and services that provide a user profile or account. For example, if a user wants to login to their
72:
271:
2722:
1738:
1698:
1584:
1150:
to check if the mailbox exists. Callback verification is an imperfect solution, as it may be disabled to avoid a
399:
94:
2734:
1343:
1089:
1085:
234:
The transmission of electronic mail from the author's computer and between mail hosts in the
Internet uses the
17:
1041:(even if escaped (preceded by a backslash), spaces, quotes, and backslashes must still be contained by quotes)
1836:
1265:
792:
235:
188:
2432:"2011-01-25 - Approval of Delegation of the seven top-level domains representing India in various languages"
1519:
However, exploiting the case sensitivity of mailbox local-parts impedes interoperability and is discouraged.
294:
727:
422:
1816:
1779:. However, the phrase is hidden, thus one has to either check the availability of an invalid ID, e.g.,
1424:
1035:(spaces, quotes, and backslashes may only exist when within quoted strings and preceded by a backslash)
381:
210:
in the form of an email address as the username ID, even though the service in this case is not email.
258:. The mailboxes may be accessed and managed by applications on personal computers, mobile devices or
1659:
2596:
Simple Mail
Transfer Protocol (Obsoletes RFC 821, Updates RFC 1123, Obsoleted by RFC 5321) (Errata)
2261:
1166:
means of delivering messages from a website, e.g., user messages, user actions, to the email inbox.
1151:
714:
part of an email address has to conform to strict guidelines: it must match the requirements for a
699:
2365:
1732:
301:) contains the name of the recipient's mailserver. In absence of an MX record, an address record (
2576:
Requirements for
Internet Hosts, Application and Support (Updated by RFC 2821, RFC 5321) (Errata)
1293:
1078:
963:(local-part ending with non-alphanumeric character from the list of allowed printable characters)
565:). Common advice is to avoid using some special characters to avoid the risk of rejected emails.
318:
2512:"देश में पहला, प्रदेश के हर नागरिक के लिए मुफ्त ई-वॉल्ट और ई-मेल की सुविधा शुरू - वसुन्धरा राजे"
2020:
1574:
1135:), although technical specification detailed in RFC 822 and subsequent RFCs are more extensive.
969:(IP addresses are allowed instead of domains when in square brackets, but strongly discouraged)
668:
2225:
1161:
Several validation techniques may be utilized to validate a user email address. For example,
1147:
514:
In addition to the above ASCII characters, international characters above U+007F, encoded as
2200:
2114:
1615:
1530:
1491:
1450:
1875:
1635:
1598:
1511:
1470:
1419:
1404:
550:
410:
The local-part of the email address may be unquoted or may be enclosed in quotation marks.
267:
2449:
8:
1951:
1429:
1355:
1349:
1186:
680:
286:
198:
Due to the ubiquity of email in today's world, email addresses are often used as regular
2497:
2273:
2056:
2556:
Standard for the Format of ARPA Internet Text Messages (Obsoleted by RFC 2822) (Errata)
1143:
1023:(none of the special characters in this local-part are allowed outside quotation marks)
684:
290:
50:
1029:(quoted strings must be dot separated or be the only element making up the local-part)
1396:
1284:
1190:
667:(plus and Subdomain Addressing), postale.io (plus), Pobox (plus), MeMail (plus), and
362:
207:
1376:
1282:
top-level domain, the government of India in 2011 got approval for ".bharat", (from
2689:
2679:
2676:
Overview and Framework for Internationalized Email (Obsoletes RFC 4952, 5504, 5825)
2669:
2659:
2649:
2639:
2629:
2619:
2609:
2599:
2589:
2579:
2569:
2559:
2549:
2539:
1865:
1742:
1702:
1625:
1588:
1501:
1460:
1312:
1300:
1225:
910:
821:
605:
576:
251:
239:
98:
2038:
1256:. RFC 6531 provides a mechanism for SMTP servers to negotiate transmission of the
2666:
A Recommendation for IPv6 Address Text Representation (Updates RFC 4291) (Errata)
1823:
1768:
1382:
1289:
722:
labels, each label being limited to a length of 63 characters and consisting of:
326:
282:
2693:
2683:
2673:
2663:
2653:
2643:
2633:
2623:
2613:
2603:
2593:
2583:
2573:
2563:
1878:
1855:
1692:
1638:
1619:
1601:
1578:
1514:
1495:
1473:
1454:
1320:
1316:
1304:
1241:
1237:
1233:
1229:
825:
609:
255:
247:
243:
106:
102:
2750:
2553:
2543:
1927:
1337:
1327:
632:
334:
2409:
1797:
1224:(EAI, also known as IMA, Internationalized Mail Address). This group produced
1045:
1234567890123456789012345678901234567890123456789012345678901234+x@example.com
806:
Comments are allowed in the domain as well as in the local-part; for example,
2744:
2718:
2707:
2636:
Simple Mail Transfer Protocol (Obsoletes RFC 2821, Updates RFC 1123) (Errata)
498:
Comments are allowed with parentheses at either end of the local-part; e.g.,
487:
The maximum total length of the local-part of an email address is 64 octets.
2353:
Verification & Validation Techniques for Email Address Quality Assurance
1127:
An email address is generally recognized as having two parts joined with an
2606:
Internet Message Format (Obsoletes RFC 822, Obsoleted by RFC 5322) (Errata)
2177:
1728:
1688:
1570:
1409:
1204:
Some companies offer services to validate an email address, often using an
628:. This can be useful for tagging emails for sorting, and for spam control.
2646:
Internet Message Format (Obsoletes RFC 2822, Updated by RFC 6854) (Errata)
2134:
Pobox supports the use of "+anystring" (plus extensions) with any address.
945:"very.(),:;<>\".VERY.\"very@\\ \"very\".unusual"@strange.example.com
1972:
1138:
Syntactically correct, verified email addresses do not guarantee that an
1121:
711:
660:
652:
644:
366:
314:
306:
163:
2616:
Application Techniques for Checking and Transformation of Names (Errata)
2300:"How Domino formats the sender's Internet address in outbound messages"
1361:
1331:
1092: in this section. Unsourced material may be challenged and removed.
788:
773:
691:
allow configuring an arbitrary separator from the legal character set.
342:
167:
1870:
1747:
1707:
1630:
1593:
1506:
1465:
1414:
1139:
656:
640:
393:
298:
203:
199:
1067:
2626:
IP Version 6 Addressing Architecture (Updated by RFC 5952) (Errata)
1257:
1208:, but there is no guarantee that it will provide accurate results.
796:
715:
664:
346:
302:
297:(RR) for the recipient's domain. A mail exchanger resource record (
1390:
553:
only allows creation of email addresses using alphanumerics, dot (
1253:
1128:
948:
694:
The text of the tag may be used to apply filtering, or to create
259:
2383:
2115:"Can I use myaddress+extension@pobox.com with my Pobox account?"
1154:, or callbacks may be reported as spam and lead to listing on a
27:
Identifier of the destination where email messages are delivered
2729:
2686:
SMTP Extension for Internationalized Email (Obsoletes RFC 5336)
2586:
Mailbox Names for Common Services, Roles and Functions (Errata)
2546:
Simple Mail Transfer Protocol (Obsoleted by RFCs 2821 and 5321)
648:
1478:
The local-part of a mailbox MUST BE treated as case sensitive.
596:
fred+@domain or even as fred@domain. For example, the address
1307:
based servers without an extension, but are permitted by the
1249:
1179:
1155:
995:
800:
772:(letters, digits, hyphen). In addition, the domain may be an
676:
636:
580:
515:
414:
385:
192:
90:
1323:. Servers compliant with this will be able to handle these:
913:, although ICANN highly discourages dotless email addresses)
109:. The term email address in this article refers to just the
1861:
1217:
757:, provided that top-level domain names are not all-numeric;
688:
672:
389:
263:
2146:
957:(% escaped mail route to user@example.com via example.org)
886:
long.email-address-with-hyphens@and.subdomains.example.com
587:
address for the purposes of determining account identity.
2021:"Plus Addressing: The Best Way to Track Spammers in 2024"
1279:
795:(which are encoded to comply with the requirements for a
719:
1244:, and continues to work on additional EAI-related RFCs.
1051:
i.like.underscores@but_they_are_not_allowed_in_this_part
2566:
Domain names, Implementation and specification (Errata)
876:(case is always ignored after the @ and usually before)
2332:
Messaging, Malware and Mobile Anti-Abuse Working Group
985:
764:, provided that it is not the first or last character.
2450:"Internationalized Domain Names (IDNs) | Registry.In"
1547:"How a simple email address makes things complicated"
183:; some mail systems even treat them as equivalent to
2244:"Exim Configuration Parameters, "local_part_suffix""
1992:"Outlook.com supports simpler "+" email aliases too"
1372:
1299:
The example addresses below would not be handled by
382:
email addresses for other networks than the Internet
384:included other notations, such as that required by
375:
John Smith <john.smith@example.org>
45:
may be too technical for most readers to understand
2174:"Dot-Qmail, Control the delivery of mail messages"
1798:"Characters in the local part of an email address"
1492:"General Syntax Principles and Transaction Model"
1451:"General Syntax Principles and Transaction Model"
2742:
2325:"M3AAWG Sender Best Common Practices, Version 3"
903:(slashes are a printable character, and allowed)
1903:"Send emails from a different address or alias"
1252:encoding, which permits the full repertoire of
1017:(only one @ is allowed outside quotation marks)
2388:Email Address Internationalization (Active WG)
1057:
803:, both a local-part as well as a domain name.
1783:, or resort to alternative displaying, e.g.,
1197:of, the sender's IP address or email address.
2272:
947:(include non-letters character AND multiple
941:(bangified host route used for uucp mailers)
113:in Section 3.4 of RFC 5322. The RFC defines
1857:Sieve Email Filtering: Subaddress Extension
206:video gaming profile, they would use their
2410:"Email Address Internationalization (eai)"
2274:"New gTLD Dotless Domain Names Prohibited"
2168:
2166:
2057:"Plus addressing and subdomain addressing"
1928:"An Overview of the Andrew Message System"
1489:
1448:
1053:(underscore is not allowed in domain part)
1002:
2355:by Jan Hornych 2011, University of Oxford
1869:
1853:
1746:
1706:
1683:
1681:
1629:
1592:
1505:
1464:
1108:Learn how and when to remove this message
1047:(local-part is longer than 64 characters)
787:, although this is rarely seen except in
73:Learn how and when to remove this message
57:, without removing the technical details.
1897:
1895:
1544:
981:(begin with underscore different syntax)
857:
583:ignores all dots in the local-part of a
191:, efforts are progressing to permit non-
2390:. IETF. March 17, 2006 – March 18, 2013
2163:
1727:
1687:
1569:
1211:
776:literal, surrounded by square brackets
361:, where the local-part may be up to 64
14:
2743:
2474:"Now, get your email address in Hindi"
1989:
1721:
1678:
1892:
1039:this\ still\"not\\allowed@example.com
600:denotes the same delivery address as
518:, are permitted by RFC 6531 when the
413:If unquoted, it may use any of these
55:make it understandable to non-experts
2262:"Instant disposable Gmail addresses"
2086:"postale.io's FAQ on sub-addressing"
1973:"Disposable addresses in Yahoo Mail"
1787:or source view, in order to read it.
1090:adding citations to reliable sources
1061:
1021:a"b(c)d,e:f;g<h>il@example.com
951:, the first one being double quoted)
874:FirstName.LastName@EasierReading.org
309:) directly specifies the mail host.
213:
97:(IETF) in the 1980s, and updated by
29:
1817:Are Email Addresses Case Sensitive?
986:Valid email addresses with SMTPUTF8
322:
24:
2533:
2226:"Postfix Configuration Parameters"
1500:. p. 15. sec. 2.4.
1459:. p. 15. sec. 2.4.
1222:Email Address Internationalization
921:List of Internet top-level domains
357:The format of an email address is
25:
2762:
2700:
1206:application programming interface
891:user.name+tag+sorting@example.com
590:
2728:
2717:
2706:
2198:
1389:
1375:
1278:For example, in addition to the
1124:validation, and fax validation.
1066:
272:Internet Message Access Protocol
34:
2504:
2498:"Universal Acceptance in India"
2490:
2466:
2442:
2424:
2402:
2376:
2358:
2346:
2317:
2292:
2266:
2254:
2236:
2218:
2192:
2139:
2125:from the original on 2020-10-03
2107:
2096:from the original on 2020-10-06
2078:
2067:from the original on 2020-10-06
2049:
2031:
2013:
1983:
1965:
1952:"Subaddressing/Plus Addressing"
1944:
1920:
1847:
1837:"Receiving someone else's mail"
1829:
1810:
1790:
1761:
1077:needs additional citations for
1033:this is"not\allowed@example.com
998:are only allowed with SMTPUTF8)
897:inbox depending on mail server)
812:john.smith@example.com(comment)
808:john.smith@(comment)example.com
504:(comment)john.smith@example.com
500:john.smith(comment)@example.com
400:Internet Engineering Task Force
195:characters in email addresses.
153:
95:Internet Engineering Task Force
1652:
1608:
1563:
1538:
1524:
1483:
1442:
1344:Traditional Chinese characters
1266:internationalized domain names
975:(IPv6 uses a different syntax)
793:Internationalized domain names
189:internationalized domain names
13:
1:
1990:Rivera, Rafael (2013-09-17).
1580:Simple Mail Transfer Protocol
1545:Morrison, Sara (2021-09-06).
1497:Simple Mail Transfer Protocol
1456:Simple Mail Transfer Protocol
1435:
939:mailhost!username@example.org
612:refers to this convention as
568:According to RFC 5321 2.3.11
491:Space and special characters
405:
236:Simple Mail Transfer Protocol
2201:"4.1.5. extension addresses"
955:user%example.com@example.org
7:
1490:J. Klensin (October 2008).
1449:J. Klensin (October 2008).
1368:
1058:Validation and verification
909:(local domain name with no
852:
279:transmitting email messages
158:
10:
2767:
2656:Internet Mail Architecture
1769:"Sign up for Windows Live"
1575:"Size Limits and Minimums"
1425:Non-Internet email address
1340:: δοκιμή@παράδειγμα.δοκιμή
1027:just"not"right@example.com
929:(space between the quotes)
768:This rule is known as the
718:, a list of dot-separated
700:disposable email addresses
616:, but it is also known as
148:An email address, such as
2366:"4.10 Forms — HTML5"
1358:: медведь@с-балалайкой.рф
705:
352:
250:, and extensions such as
117:more broadly as either a
1152:directory harvest attack
1146:for the domain or using
992:I❤️CHOCOLATE@example.com
901:name/surname@example.com
726:Uppercase and lowercase
455:!#$ %&'*+-/=?^_`{|}~
421:uppercase and lowercase
319:electronic mailing lists
266:protocol and either the
2039:"Addresses and Aliases"
1741:. sec. 4.5.3.1.1.
1621:Internet Message Format
1616:"Address Specification"
1294:Government of Rajasthan
1003:Invalid email addresses
933:"john..doe"@example.org
882:(one-letter local-part)
869:very.common@example.com
647:Plus (hyphen), Apple's
635:(plus), Runbox (plus),
598:joeuser+tag@example.com
506:are both equivalent to
482:"John..Doe"@example.com
478:"John.Doe."@example.com
474:".John.Doe"@example.com
339:spoofed email addresses
337:addresses (also called
2712:Validate Email Address
2518:(in Hindi). 2017-08-18
1854:Murchison, K. (2008).
1826:by Heinz Tschabitscher
1334:: éléonore@example.com
816:john.smith@example.com
508:john.smith@example.com
156:, the symbol @, and a
150:john.smith@example.com
129:value can be either a
1660:"Spotting a Spoofing"
1587:. sec. 4.5.3.1.
1364:: संपर्क@डाटामेल.भारत
1362:Devanagari characters
1148:callback verification
895:user.name@example.com
858:Valid email addresses
465:John..Doe@example.com
453:printable characters
141:, or the more common
2737:at Wikimedia Commons
2304:IBM Knowledge Center
2260:Gina Trapani (2005)
1420:Email authentication
1405:Anti-spam techniques
1288:), written in seven
1212:Internationalization
1187:heuristic algorithms
1086:improve this article
570:Mailbox and Address,
551:Windows Live Hotmail
341:) are often seen in
287:mail transfer agents
268:Post Office Protocol
152:, is made up from a
2500:. 15 February 2017.
1666:. November 19, 2020
1430:International email
1356:Cyrillic characters
1350:Japanese characters
935:(quoted double dot)
681:Courier Mail Server
602:joeuser@example.com
293:(DNS) to look up a
238:(SMTP), defined in
133:, which contains a
2478:The Economic Times
2436:features.icann.org
2384:"Eai Status Pages"
2180:on 26 January 2012
2119:helpspot.pobox.com
1822:2016-06-03 at the
1191:statistical models
1144:Domain Name System
893:(may be routed to
864:simple@example.com
814:are equivalent to
291:domain name system
229:jsmith@example.com
2733:Media related to
1691:(February 2004).
1624:. sec. 3.4.
1397:technology portal
1290:different scripts
1272:representations.
1118:
1117:
1110:
1015:a@b@c@example.com
961:user-@example.org
917:example@s.example
622:tagged addressing
543:JohnS@example.com
539:johns@example.com
380:Earlier forms of
359:local-part@domain
262:sites, using the
214:Message transport
208:Microsoft account
179:as equivalent to
162:, which may be a
83:
82:
75:
16:(Redirected from
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2176:. Archived from
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2061:www.fastmail.com
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1998:. Archived from
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1748:10.17487/RFC5321
1731:(October 2008).
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1573:(October 2008).
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1285:Bhārat Gaṇarājya
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577:case sensitivity
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467:is not allowed).
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626:mail extensions
618:plus addressing
593:
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558:
557:), underscore (
554:
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538:
534:
533:The local-part
507:
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493:"(),:;<>@
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295:Resource Record
289:(MTAs) use the
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51:help improve it
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28:
23:
22:
15:
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2723:Best Practices
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2701:External links
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1996:Within Windows
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633:Andrew Project
592:
591:Sub-addressing
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561:) and hyphen (
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323:sub-addressing
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89:identifies an
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18:E-mail address
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2516:वसुन्धरा राजे
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2022:
2016:
2002:on 2014-02-20
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1075:This section
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365:long and the
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315:Email aliases
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270:(POP) or the
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43:This article
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32:
31:
19:
2725:at Wikibooks
2714:at Wikibooks
2520:. Retrieved
2515:
2506:
2492:
2481:. Retrieved
2477:
2468:
2457:. Retrieved
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2444:
2435:
2426:
2416:November 30,
2414:. Retrieved
2404:
2392:. Retrieved
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2336:. Retrieved
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2307:. Retrieved
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2282:. Retrieved
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2256:
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2238:
2229:
2220:
2208:. Retrieved
2204:
2199:Sill, Dave.
2194:
2182:. Retrieved
2178:the original
2154:. Retrieved
2150:
2141:
2133:
2127:. Retrieved
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2109:
2098:. Retrieved
2089:
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2069:. Retrieved
2060:
2051:
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2033:
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2004:. Retrieved
2000:the original
1995:
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1955:. Retrieved
1946:
1934:. Retrieved
1922:
1910:. Retrieved
1906:
1882:. Retrieved
1856:
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1763:
1752:. Retrieved
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1712:. Retrieved
1693:
1668:. Retrieved
1664:cyber.nj.gov
1663:
1654:
1642:. Retrieved
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1554:. Retrieved
1550:
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1535:, Google.com
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1410:Email client
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1084:Please help
1079:verification
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2454:registry.in
2230:postfix.org
1912:13 December
1884:February 9,
1729:Klensin, J.
1689:Klensin, J.
1571:Klensin, J.
1352:: 二ノ宮@黒川.日本
1122:postal mail
973:postmaster@
967:postmaster@
847:example.org
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