If Windows Update is stuck (especially on 0%) for at least 30 minutes, it is possible that your Windows PC has insufficient hard drive space to complete the updates. To determine this, you will need access to a second hard drive or a second computer.
With access to a second computer, you can place your hard drive that is having the issue as a slave or secondary drive inside. Do not worry if the motherboard does not support adding a second hard drive as you should be able to use the data and power cable for your optical drive temporarily so you can see the capacity of the troubled hard drive in Windows Explorer.
Second Hard Drive
If you can not get access to a second computer, the next best thing is to get your hands on a second hard drive with the same OS and matching Legacy or UEFI firmware setting and boot it with your troubled drive as a slave or secondary hard drive. If you have a mirror copy of your hard drive, this will be perfect as it will save you up to an hour installing the Operating System and programs and all you need to do is upload your data.
Before powering up your backup drive, please remove the Ethernet cable so the computer can not go online to check for Windows Update. If you get the message of a hard drive not found when booting the hard drive, you will need to check your setting in the BIOS and cables once more.
Run Disk Cleanup on your hard drive frequently. Windows update files are removed after 30 days to give you the chance to roll back but this also eats up your hard drive resources so put it on your calendar of things to do.