Outlook 2011 sending email issue on MAC OSX 10.6.8

Hi, I have recently installed outlook on my mac and configured my emails, it has been working fine (so not the smtp settings) until recently, when I try sending emails,  I receive this error code (incoming emails are fine)

An operation on the server timed out. The server may be down, overloaded,
or there may be too much net traffic. Error code 3259

I am running MAC OS X 10.6.8. Windows installed 2011 14.1 (cannot upgrade to 14.3 for some reason)

I have searched the net and found this top that suggests changing port to 587, (http://support.microsoft.com/kb/2443563)

It doesn't work

I have spoken to my host and they have suggested setting authentication to same as incoming server. Firewall is off.

This doesn't work either.

Since this I have run macbook cleaner to hopefully get rid of any errors. I've also built a new account reinstated outlook and my account settings, problem still happening though.

Ive also read a post that suggest upgrading to the new Safari 5.1.7, installed and that (not surprisingly) hasn't fixed it

Please, if anybody has any ideas how to fix this problem would be appreciated. I have purchased outlook especially to use and it has been working fine. I've now spent a week trying to fix arrrgh!

Thanks