So both TB and OE do this? Hmmmmm..... Then it's not likely the email program.

Do you have 'webmail' access? That is, can you log into your email via a webpage on the ISP? You probably can, but you might not have known about it.

Which, if you can't even log in to your ISP account, that's a big clue right there that it's on their end.

Brian