| Microsoft Outlook (MSG) | 97 – 2019 | |
| Microsoft Outlook Express (EML) | 97 – 2019 | |
| Microsoft Outlook Forms Template (OFT) | | |
| Microsoft Outlook OLM | 2011 for Mac | File ID only |
| Microsoft Outlook OST | 97 – 2019 | |
| Microsoft Outlook PST | 97 – 2019 | |
| Microsoft Outlook PST (Mac) | 2001 | |
| MSG with Digital Signature | SMIME | |
| EML with Digital Signature | SMIME | |
| Apple Mail Message | | File ID only |
| IBM Lotus Notes Domino XML Language DXL | 8.5 | |
| IBM Lotus Notes NSF | 7.x, 8.x | File ID only |
| IBM Lotus Notes NSF | 8.x | Win32, Win64, Linux x86-32, Solaris8 (Notes Client or Domino Server required) |
| MBox Mailbox | RFC 822 | File ID only |
| Encoded mail messages | MHT | |
| Encoded mail messages | Multi Part Alternative | |
| Encoded mail messages | Multi Part Digest | |
| Encoded mail messages | Multi Part Mixed | |
| Encoded mail messages | Multi Part News Group | |
| Encoded mail messages | Multi Part Signed | |
| Encoded mail messages | TNEF | |