Unable to get Active Directory accounts authenticated via the WEB CLIENT on version 10.0.0+ -->
Error:
"The connection to server "fqdn" was aborted with the error: Login failed, reason: User does not exist in Active Directory. Contact support. Do you want to try reconnecting?"
We were able to fix our issue by RDPing into the VC server --> Open the client --> Login in as "admin" (localhost) --> Settings --> Web Client --> Uninstall the IIS webclient --> give a few to complete --> reinstall the webclient --> give it a few to complete
We inspected IIS settings and could not find where it was erroring. So we "started over" with the web client and it helped our login issue.