Explicit EAP error 0x9009030C. Authentication failed due to a user credentials mismatch on NPS server

[ronnieshih]

We've been having a strange problem related to 802.1x authentication using internal CA certificates against a wireless network that uses 802.1x authentication. Most of the computers don't have issues but this problem crops up on newly setup machines which have acquired internal certs for 802.1X authentication recently. The Explicit EAP error 0x9009030C pops up from the endpoint Windows 11 pc end. On the Windows NPS RADIUS server side, we see eventlog ID 6273 "Authentication failed due to a user credentials mismatch. Either the user name provided does not map to an existing user account or t

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