Mozilla Firefox Page Load Errors

Hi. Here's what's happening;
Receiving many "Page Load Errors" and "Server Not Found" when on the internet. I use Mozilla Firefox, so I went on their website and read a few posts in the forums. Apparently many people started having this problem after Mozilla Firefox updated to version 3.5.5. The solution listed was this:
"A possible cause is security software (firewall) that blocks or restricts Firefox without informing you about that, maybe after detecting changes (update) to Firefox program. Remove all rules for Firefox from the permissions list in the firewall and let your firewall ask again for permission to get full unrestricted access to internet for Firefox."
I have McAfee Security, so I went into the Permissions list and Firefox is listed as having "Full Access". So I blocked the access, then put it back on, but this did nothing to solve the problem. So I'm stuck at this point. Plus, the more I read about the "permissions" thing, the more confused I get! Thanx for any help!

I do not use any McAfee garbage, but look under applications, should be there, and as they, remove the firefox stuff.
Now start over.

It worked. Things are moving right along, just fine--Thank you!

You are Welcome and thanks for posting back!