| 1 | ABX | Corel Corporation | Corel WordPerfect Mail Address Book |
| 2 | BOE | Microsoft Corporation | Microsoft Outlook Express Backup |
| 3 | DBX | Microsoft | Outlook Express E-mail Folder |
| 4 | EMAIL | Microsoft | Outlook Express Email Message |
| 5 | EML | Microsoft | E-Mail Message |
|
| 6 | EMLX | Apple | Mail Message |
| 7 | LDIF | N/A | LDAP Data Interchange Format |
| 8 | LIST | Oracle | JAR Index Format |
| 9 | MAB | Mozilla | Mozilla Address Book |
| 10 | MAILHOST | Microsoft | MSN Mailhost Settings Format |
| 11 | MBOX | N/A | E-mail Mailbox Format |
| 12 | MBS | Opera Software | Opera Mailbox Format |
| 13 | MBX | Microsoft | Outlook Express Mailbox |
| 14 | MSB | RITLabs SRL | The Bat! Format |
| 15 | MSG | Microsoft | Outlook Mail Message |
| 16 | NWS | Microsoft | Windows Live Mail Newsgroup Format |
| 17 | OAS | rsbr Software | Microsoft Outlook Attachment Sniffer |
| 18 | OLK14MSGATTACH | Microsoft Corporation | Microsoft Outlook 2011 For Mac Message Attachment |
| 19 | P10 | N/A | Certificate Request Format |
| 20 | P7Z | N/A | S/MIME Compressed Message |
| 21 | PAB | Microsoft | Personal Address Book |
| 22 | PMI | David Harris | Pegasus Mail Message Folder Index |
| 23 | PMM | David Harris | Pegasus Mail Mailbox Format |
| 24 | PST | Microsoft | Outlook Personal Information Store Format |
| 25 | RPMSG | Microsoft | Outlook Restricted Permission Message |
| 26 | SBD | Mozilla | Mozilla Mail Subdirectory Format |
| 27 | TNF | Microsoft Corporation | Transport Neutral Encapsulation Format |
| 28 | VCARD | Apple, Inc. | VCard |
| 29 | VCF | N/A | VCard Format |
| 30 | VRGE08CONTACT | Microsoft Corporation | Microsoft Entourage 2008 Contact |
| 31 | VRGE08EVENT | Microsoft Corporation | Microsoft Entourage 2008 Event |
| 32 | VRGE08GROUP | Microsoft Corporation | Microsoft Entourage 2008 Group |
| 33 | VRGE08MESSAGE | Microsoft Corporation | Microsoft Entourage 2008 Message |
| 34 | VRGE08NOTE | Microsoft Corporation | Microsoft Entourage 2008 Note |
