To confirm you are experiencing this issue, two conditions must be true:
1. You must have an OEM install. If you installed off of retail media and WSUS is not installing on your SBS for any reason, I want to
hear from you
, but the fix above probably isn't what is preventing WSUS from installing.
2. Look at your
in the Program filesUpdate ServicesLogFiles of your install drive. Affected machines will show an error similar to the following :