Error message when you try to establish a dial-up VPN connection that uses EAP-TLS for authentication in Windows Vista: "Error: 0x80420100: There was an unknown error"

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Symptoms
On a computer that is running Windows Vista, you try to establish a dial-up virtual private network (VPN) connection that uses Extensible Authentication Protocol-Transport Layer Security (EAP-TLS) for authentication.

If there are no user certificates on the computer, you may receive the following error message:
Error: 0x80420100: There was an unknown error.
Properties

Article ID: 947209 - Last Review: 01/16/2015 17:33:59 - Revision: 2.0

Windows Vista Enterprise 64-bit Edition, Windows Vista Home Basic 64-bit Edition, Windows Vista Home Premium 64-bit Edition, Windows Vista Ultimate 64-bit Edition, Windows Vista Business, Windows Vista Business 64-bit Edition, Windows Vista Enterprise, Windows Vista Home Basic, Windows Vista Home Premium, Windows Vista Starter, Windows Vista Ultimate

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