There is a very specific reason for this problem
How to Upgrade Windows 7 Home, Pro to Ultimate
One of my customers ran into a problem when they tried to upgrade from Windows 7 Home Premium to Professional using the Windows Anytime Upgrade tool. Instead of it working as normal, they got the following message:
The only pitiful solution it gives you is to retry the upgrade, which doesn't work. Clicking the Go online to fix this problem link doesn't seem to get you anywhere either. After some research I figured out what the problem was and was finally able to upgrade the customer's PC. Basically it was because Windows Update had downloaded Service Pack 1 onto the computer, but it wasn't installed by the customer. Therefore Windows Anytime Upgrade thinks this is some kind of partial installation and blocks the upgrade.
In this article I will guide you through the possible solutions. If you are still having problems or getting this error, post a comment here and I will try to help.
