The problem is probably not with Outlook Express but with your e-mail server. Do you use a web based program such at Hotmail or Gmail, or do you use a service provided by your ISP? Definitely need more information here before any help can be rendered.

Yes! And there should be some sort of error code generated is there?

Don't know about Outlook Express, since mine is Outlook.

In Outlook, if accidently set it 'work offline', it won't send mails out. The 'work offline' option is under 'FILE'.

I had multiple phone/comp. problems untill the man replaced the line TO THE HOUSE. Lost OE completely and was irked! I kept restoring system and it came back WITH O.E.
Of course , you have to do SOME updating SOMETIMES after a restore. That was the only fix this old man knew to do and wasn't sure that it would cure my ills, but it did. I've used O.E. for so long that I just hate to TRY and go to another e mail program.

Your phone or cable line being replaced has nothing to do with Outlook Express.

I would suspect that if you've done multiple restores a setting got changed somewhere.

What happens when you try to send an email? Do you get any kind of error messages?