After a new installation of Windows 7, Windows Update simply won’t work as it stalls during the check for updates.
A bug in the Windows Update client is the cause and it’s triggered when there are a lot of updates to process.
This is resolved by applying the KB3172605 update. However, installing this update can also take a long time as the ‘bug’ is still there!
The below procedure will get things moving.
Download the appropriate (x64 or x86) versions of the below three updates and save them somewhere handy.
http://catalog.update.microsoft.com/v7/site/Search.aspx?q=KB3125574
http://catalog.update.microsoft.com/v7/site/Search.aspx?q=KB3172605
http://catalog.update.microsoft.com/v7/site/Search.aspx?q=KB3020369
Open an elevated command prompt and run the following command:
net stop wuauserv
Navigate to c:\windows\softwaredistribution\WuRedir and delete all files and folders.
Run the KB3020369 update – should take a couple of minutes.
Stop the Windows Update Service again with the net stop wuauserv command
Now run the KB3172605 update you previously downloaded. Follow the prompts. Reboot when it says to. (This step should take about 1 minute).
Stop the Windows Update Service again with the net stop wuauserv command
Run the KB3125574 update. This will take longer to install and will require a reboot.
Once rebooted and back into Windows run Windows update again.
Reboot as required and run Windows update again until no updates are available.