OE Classic is a freeware / shareware e-mail client. It was written in 2010 with the idea of replacing Microsoft's aging Outlook Express 6, with a new and current e-mail client supporting the latest security, but having a very similar look-and-feel to Outlook Express's simple yet powerful interface. It runs on Windows from Windows 2000 and XP to Windows 10, and supports POP3, SMTP and IMAP. 
As of January 2020, many ISP's have begun to drop the TLS 1.0 protocol from IMAP and POP3 accounts. Due to Outlook Express not supporting anything newer than TLS 1.0, problems sending and/or receiving mail may now be experienced. OE Classic however, still supports TLS 1.0, as well as the new TLS 1.1 and TLS 1.2.
- "OE Classic discussions and updates" (in en-US). https://www.wilderssecurity.com/threads/oe-classic-discussions-and-updates.393261/.
- "Anyone using OE Classic for email? - Windows 10 Help Forums" (in en). https://www.tenforums.com/browsers-email/51700-anyone-using-oe-classic-email.html?s=19c1d07655c8c54ee6ed8ed3e2f139f5.
- "OE Classic Alternatives and Similar Software - AlternativeTo.net" (in en). https://alternativeto.net/software/oe-classic/.
- "Outlook Express Error 0x800CCC0B and the End of TLS 1.0 (Deprecated SSL Protocol) | Joe Wein's blog" (in en-US). https://joewein.net/blog/2018/07/04/outlook-express-error-0x800ccc0b-and-the-end-of-tls-1-0-deprecated-ssl-protocol/.