imap stopped working when I changed network

Hi,
I recently did a fresh install of Windows 7 Enterprise 64bit at work. I installed it behind a nat:ed machine (internal IP), so nothing special about that one. I chose home network as the network type as I would be using the computer at home from now on.

However to my surprise, when I got home the email had stopped working. Everything else is working just fine. The problem is with thunderbird (or other email programs) and imap. If I try to check my new emails at home I just receive a message that connection to imap.xxx.xx.xx has timed out. This was working just fine when the computer was at work.
Home network is similar, broadband connection, connected to Buffalo WHR-G54S (NAT, DHCP). I've checked about everything and I have no clue what to do next. It doesn't matter if I turn the windows firewall completely off, I still get the same results (time out).
HOWEVER, I discovered a new thing. If I'm connected via VPN to my work network, I can check my email from home. Weird stuff, where the hell has windows stored something about my work connection here at home?

/J

You'll probably have to set it up again adding in all the entries.

I've deleted/uninstalled the network driver and hoped for windows to ask all the questions again. But no, it just installed the driver again asking no questions whatsoever.

What would be your solution for setting it up again?