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WU_E_PT_HTTP_STATUS_BAD_REQUEST
WU_E_PT_HTTP_STATUS_BAD_REQUEST maps to HTTP 400: the server could not process the request because its syntax was invalid. In a managed environment, check the update-service URL and any proxy or gateway that could rewrite requests.
What to check
- Verify the WSUS endpoint configured by policy and compare it with a working client.
- Inspect proxy, reverse-proxy, or web-filter logs for the rejected request.
- Correlate the HTTP 400 with SOAP or client-version errors that explain why the request was rejected.
Microsoft: WUA networking error codes
Microsoft: Windows Update troubleshooting
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