Have trouble installing updates from Windows Update? Check out the Windows Update Troubleshooter/Reset Tool written by the Fix-It Team at Microsoft. This tool resolves most of the Windows Update and Automatic Update issues by resetting the Windows Update configuration.
Note: Windows 8 and 8.1 version of the troubleshooter can be downloaded from this page.
Windows Update Troubleshooter tool for Windows 10
Download Windows Update Troubleshooter for Windows 10 (WindowsUpdateDiagnostic.diagcab), and run the file.
Click Advanced, and click Run as administrator.
The troubleshooter does various checks to determine if Windows Update components have any problems.
You can check the detailed report by clicking View detailed information.
Windows Update Reset (Fix It) Tool for Windows Vista & XP
Download Windows Update Reset (Fix It) Tool.
This tool automates the most common fixes (including DLL registration) to issues with the Windows Update site. This Fix it Solution has two modes Default and Agressive. You should run the Fix it solution in Default mode and determine if it resolves your problem with Windows Update before running it in Agressive mode.