Lots of complaints about Windows 7 Update being broken or not working right. What happens is that when you select to run Windows update, it will just sit their spinning for hours on end. Some people have left it running for 24 hours.

So frustrating. I know. BTDT.

So, here are the steps that I follow to fix the Windows 7 Update issue:

1. Set Windows Update to not update
   Open up Windows Update, click on Change Settings, then click to NOT update
   
2. Stop the Windows Update service
   You can do this by running services.msc
   Then locate and right click on the Windows Update service, then click to STOP  the service.
3. Delete certain files from the Software Distribution folder
   Open up File Explorer and drill down C:/Windows/SoftwareDistribution
   Open up the Download subfolder and delete all files within the folder
   Go back a level, open up the DataStore folder and delete all the files within the folder
4. Download the July 2016 Windows 7 Update Rollup (KB 3172605)
   Open Internet Explorer and go to https://support.microsoft.com/en-us/kb/3172605 
   Scroll down to Method 3 (Microsoft Update Catalog)
   Click on the link and install the Microsoft Update Catalog utility
   Click to select the appropriate download for Windows 7
   Click to View Basket in the top right
   Verify the selected file then click Download
   Select the location to download the file
5. Install the July 2016 Windows 7 Update Rollup, then Reboot
   Use File Explorer, locate the download file, then double click to run/install it
   Follow the prompts to install it
6. Reboot your computer
   Rebooting your computer will make sure that the Windows Service is restarted properly
7. Rerun Windows Update
   Hopefully it will now work for you