I want to test my software on different Windows Operating Systems. I plan to do it using Virtual Machine software, either VMWare or Microsoft Virtual PC.
I would like to be able to test Windows 7, Windows Vista, Windows XP and Windows 98 in both 32 and 64 bit flavors, and possibly at differing service pack levels.
Where can I get the Images or full OS's, either free or by purchase, to run on either of these VM systems?
Update, June 2015: Microsoft is retiring the TechNet Subscription service and replacing it with the TechNet Evaluation Center. So romandas' answer is no longer valid. I'm moving the accepted answer over to Michael Burr, whose link still provides a good number of OS images, and for free as well.
The original post about the "test" VPC images Microsoft provided is obsolete.
As far as I know, the only publicly available VM image Microsoft makes available as of this writing (24 Oct 2024) if for Win 11 Enterprise with a some developer tools/configuration included (such as VS 2022 and WSL2 qith an Ubuntu image):
Unfortunately, as of this writing there is also a message that says
Due to ongoing technical issues, as of October 23, 2024, downloads are temporarily unavailable.
Hopefully the technical issues are truly temporary...