error message 0x800ccc0f in microsoft 2010

When ever I try to send an email I get the following error message in outlook 2010. operating system is windows 7 64 bit I’ve changed stuff in avast to no avail. Could someone guide me with simple step by step instructions to get my email working. My verison is 7.0.1474 and I’m using the trial version at the moment. If I cant get this working I dont know want to do, as mcafee caused a trojan to get thru and & crashed my computer.

Why don’t you just check your email via Yahoo.com? AT&T uses Yahoo email. Its web based email which means there is no need to use Outlook. Does Outlook work with Avast disabled? Did you allow your Yahoo email to be forwarded via POP?

If I cant get this working I dont know want to do, as mcafee caused a trojan to get thru and & crashed my computer.
No security program have 100% detection have you cleaned your computer?

Thank you all for your replies. I got it working late last night.