Try running DISM and SFC commands to repair Windows system files. Once complete reboot and try running the update again.
DISM /Online /Cleanup-image /RestoreHealth SFC /Scannow
DISM (Deployment Image Servicing and Management) manages both Windows Online and Offline Images and repairs system files
- /Online switch instructs DISM to target the running Operating System instead of an offline Windows image (.wim) file or virtual hard disk (.vhd or .vhdx)
- /Cleanup-Image switch performs cleanup and recovery operations on the running Operating System
- /Restorehealth switch scans the running Operating System for corrupt files and attempts to fix them
SFC (System File Checker)
- /Scannow will scan all protected system files, and replace corrupted files with a cached copy that is located in a compressed folder at %WinDir%\System32\dllcache
The above procedure also fixes Windows Defrag not running properly due to corrupt system files.