Btw have you tried repairing with Windows repair? Could be software distribution folder
I also tried this procedure:
1) Disabled Windows update Service
2) Deleted all files in c:\windows\softwaredistribution\datastore and deleted files in c:\windows\softwaredistribution\download
4) 3) Downloaded and installed the most up to date Windows Update Agent.
5) Restarted Windows Update Agent, made sure Workstation and Background Intelligent Transfer Services were running.
6) Ran the MS Mr. Fixit program to repair update issues.
7) Ran the Windows update. 21 updates to install (as always).
8) Rebooted
9) Guess what, same issue!