Anyone who is using the non-embedded version of the PSC appliance might notice that using Windows Session Credentials does not work when logging into vCenter with the C# client. The problem here is that even if the PSC is joined to the domain, the appliance VM housing the Web Client and vCenter is not. See here if you still need to join the PSC to a domain.
Note: If you encounter this with an embedded PSC, try this VMware KB article
You will see error messages such as:
Windows Session credentials cannot be used to log into this server.
A general system error has occurred: Cannot get user info
To fix this, the vCenter Server Appliance also needs to be joined to the domain.
Step 1. Access the CLI of the vCenter Server Appliance with SSH.
shell.set --enabled True
Step 2. Join the external standalone vCenter Appliance to AD with domainjoin-cli
/opt/likewise/bin/domainjoin-cli join domain user
/opt/likewise/bin/domainjoin-cli join vlimitless.local Administrator
Step 3. Reboot the Standalone vCenter Appliance to apply the changes