could anyone indicate me a good E-Mail server to use under windows? I need to test validation without needing the webhost... (for the record, I'm not in linux because I have my reasons, which does not include being lazy)
Try Mercury Mail Server at this LINK and it should work put for you. It is not really all that easy to setup unless you have done so before, but with a small amout of effort it will work. I played with it on my intranet and got it working and you might want to also use the E-Mail client Pegasus.
I use Smarter Mail for my mail service on my windows boxes you can get a free version for 1 domain at smartertools.com it is extremly easy to set up & is the best mail system I have found and I looked at just about all of them.