I have a test copy that I run on my Win2k box at home from time to time. I use a sendmail program for windows that I found at http://www.indigostar.com and I use the same incoming pop account that we use with the live version. I haven't had any problems with it at all. What kind of problems are you having? I do use Apache and MySQL for windows though.
Regards,
Charlie
Regards,
Charlie