Ian McCulloch wrote:

snip - describes regedit to remove block on .tmp filetype

All of which only helps YOU when *receiving* e-mails. Just how is you
unblocking .tmp files going to do anything for the recipient who might
also be blocking on .tmp files?

When I attach "hazardous" files, Outlook warns me. It doesn't strip the
attachment. If I heed the warning and do not attach then there is no
attachment to strip out. If I ignore and attach the file anyway,
Outlook attaches the file and sends it despite the warning that the
recipient may not be able to use the attachment.