My outlook express receives mail, but I'm not able to send
one. POP and SMTP server settings are okay, and this
problem is not because of any outlook express setup, since
the same set up was functioning well till the other day.

Also, I'm not able to connect to any web-based email pages
as well (hotmail, yahoo, netscape, etc.,). They accept my
login credentials, but the messaage pages never appear
(server timed out / server not found). Same pages work
well if I access them from other computers.

I guess some of the services that I have disabled/stopped
in the controlpanel->performance->administrative tools- 
them back, but I don't know which one(s).

If anyone can help, I would much appreciate it!

OS: Win XP professional with SP1.