How Do I Fix Windows Defender Error Code 0X800B0109?

How do I fix error code 0x800b0109?

Error 0x800b0109 usually occurs when a file needed by Windows Update is corrupted or missing. We suggest that you use the System File Checker tool to repair damaged Windows files.
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Kindly follow the steps below:

1. Open an elevated command prompt.
2. Run the “sfc /scannow” command.
3. Try to install update again.

What is error code 0x800b0109?

Correct 0x800b0109 = A certificate chain processed, but terminated in a root certificate which is not trusted by the trust provider. This means the client doesn’t trust the certificate you used to sign the update files.