I have been battling Windows Update Error 800B0100 for over a week. I searched the web over and over and tried pretty much every solution presented. I don't know how many times I ran the Windows Readiness Tool, update fixer, fixer fixer, Mr. FixIt, delete this, delete that, uninstall all of these, manually install those, etc.
Nothing made it work. I finally just blew away the VM - this was Windows 7 Professional on my Mac, and did a reinstall from DVD. After many updates it all appears to be working. I have never run into this sort of issue in the past where Windows got so messed up that I had to give up.
Another odd thing, I needed .NET 4.0 so I download that. Right away I have to download 16 patches. This means MS does not keep the installer updated. Must be the original install then you have to download all the patches. Seems a waste of bandwidth to me. I should get a pretty recent version of the .NET 4.0 installer when I download it. I don't expect to download Chrome, 7Zip, Sublime Text or others just to turn around and have its updater run and get more stuff. To me it makes MS appear lazy.
At least it is up and running now. I needed to install IIS but with the update issue that was not possible as the windows features list just came up empty. Now it fills in and I could install IIS. Turns out that was for naught because the final piece of 3rd party software was holding all its errors and only showing me one at a time. It complained about IIS but once that was installed it turned around and told me my OS was not supported. Gee, seems that is a much more important error message. You really should from the worst situation forward or show a list of issues instead of just the first one you find.
Now we have to find and configure a Win Server 2008 to get this all rolling. Guess I will go back to some iOS clean up coding while I wait for that to happen.