I've not experienced these symptoms as such!
But after my recent format every single version of eMule I loading would bomb out in the exact same way as you are mentioning except that it was on instant connection to a server.
eMule would sit there happily for hours idle, but as soon as I clicked connect it bombed out
The fix that worked for me was to fully update my windows 2000 with all the service packs and windowsupdates!
I have no idea what fixed it but I kept logging on to windows updates till all were completed and then eMule worked
So are you upto date on your patches?
maybe some-one knows more information, but thats my advise, it worked for me
