Hay I have the same problem as the first message (MSN wont connect error : 10056). I can rule out a few things but I still can fix it.

I run NO firewall, The proxy does, but a different computer running trillian can still connect, I cant. The proxy settings hav not been altered since it worked in the past.

I downloaded MSN messenger (from MSN.com) and it wont connect it tries then goes UNABLE TO CONNECT, make sure your connected to the internet. blah blah blah.

I have tried playing with it but no luck. For me all this trouble started 2 days after I installed Patch D, I have now uninstalled trillian and reinstalled it, with no patches but no luck.

If u can fink of nefing I hav missed or hav any I deas what might be causing it reply PLZ!!!