I run Outlook 2007 on a Windows Vista desktop machine and it has stopped working correctly. It won't download messages for any of my accounts--when I "send and receive" the Outlook Send/Receive Progress box displays that errors occurred. (Also when I try to send a message, the message goes to the outbox and just stays there.)

I still have Web access--no problem there. And Outlook on my laptop (Windows XP, Outlook 2003) is working fine; it shares the router with the probematic desktop.

Problem started yesterday suddenly. I have replaced the pst file with the backup pst file from Sunday (my most recent backup) and that does not help.

Any advice appreciated.

It took hours to figure out, but it turns out that the firewall in Trend Micro was set up to block outgoing messages from Outlook. Something happened to trigger the block--who knows what.

Onward and upward.