A few errors with Windows Updates don't allow the Windows Update service to initiate while others halt the process while it's running. Of the many errors with Windows Updates, one is Install error 0x80070020.

This cause behind this error is installed programs interfering with the Windows Update process. It could be an anti-virus program, or a malware, or a PUP. The reason could also be missing files in the system.

1] Clear contents of SoftwareDistribution & catroot2 folders

2] Use the Windows Update Troubleshooter

3] Manually Reset Windows Update components

4] Disable the anti-virus software temporarily

5] Install in Clean Boot State

6] Restart the Windows Update Services

Read more on https://www.thewindowsclub.com/windows-update-install-error-0x80070020

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