Send attachments in Rich Text format or ASCII text format. Outlook 2000 Tools menu, click Options.
Click Mail Format tab, ensure Plain Text is default selected in Send in this message format: drop-down (An "rtf" can still send).
If sending e-mail w/ attachments to recipient who does not use Outlook or Exchange Client, manually choose a mail format that does not require Transport Neutral Encapsulation Format (TNEF) - such as plain text. By not sending TNEF messages, recipient will be able to view & save the attachments.
Outlook Express does not understand TNEF, but will ignore TNEF info. Result is plain text message discarding the winmail.dat attachment that encapsulated any user attached files.
Click Security tab, verify that Secure e-mail has NOT been set-up (i.e., is "grayed" out).
Whether Secure e-mail has been set-up, click Setup Secure E-mail, ensure that S/MIME is selected in the Secure Message Format: drop-down.
Sending secure messages over Internet, use a digital ID that is S/MIME compatible. Obtain S/MIME digital ID from your Microsoft Exchange Server administrator or from a certifying authority like Verisign.
If Exchange digital ID not S/MIME compatible, set up S/Mime security setting to send secure messages from Exchange to Internet recipients. Set-up security settings on the Tools menu, click Options, click Security tab, click Setup Secure E-mail.
Click Internet E-mail tab, verify MIME is selected under Internet E-mail sending format. None should be selected in Encode text using: drop-down.
Problem: Recipient receives Winmail.dat attachment.
Solution: Turn TNEF off (either for the recipient, or globally).
Problem: Recipient receives ATT00001.DAT attachment.
Solution: Turn TNEF off (either for the recipient, or globally).
Problem: Recipient receives no regular file attachments.
Solution: Turn TNEF off (either for the recipient, or globally).
