outlook 2003 blocked mht attachment sending out

[IT]

when our outlook forward "mth" attachment file type email , our outlook 2003
auto blocked the attachment , our user received message without attachment.

 

[Roady [MVP]]

Outlook does not remove any attachments upon sending. Not even when their
extension is on the unsafe list.
It either got removed because of company policy, a virus scanner or you are
sending in RTF format and the recipient is outside your own network (and the
mail servers in between are not configured properly to convert RTF messages
to HTML messages).