Hello
Thank you for posting in Q&A forum.
Here are some steps you can take to troubleshoot:
- Ensure that both the CA certificate and the client certificate are valid and not expired. Verify that the certificates are correctly installed on your workstation.
- Make sure the server certificate on the VPN server has the "Server Authentication" EKU. You can check this by running mmc, adding the "Certificates" snap-in, and inspecting the certificate details under "Enhanced Key Usage".
- Ensure that the trusted root certificate for the server certificate is present on your workstation. If the root certificate is missing, import it into the trusted root certification authorities store.
- Verify that the VPN server name provided on the client matches the subject name of the server certificate.
- Temporarily disable any firewall or antivirus software to see if they are interfering with the VPN connection.
References:
Error 13801, IKE authentication credentials are unacceptable
KB23221 - '13801: IKE authentication credentials are ... - Ivanti
I hope the information above is helpful.
If you have any questions or concerns, please feel free to let us know.
Best Regards,
Daisy Zhou
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