Hello @jchipoco ,
Welcome to Microsoft Q&A Platform. Thanks for posting your query.
As mentioned here, when the connection is initiated, the VPN client adds the session credentials and the failure occurs. After the connection is established, the client is forced to use the cache credentials for Kerberos authentication. To work around the problem, disable the caching of domain credentials from the following registry subkey:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa\DisableDomainCreds - Set the value to 1
Hope this helps!
Kindly let us know if the above helps or you need further assistance on this issue.
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