So, this error is not related to the OS. Check the logs. From the Help link:
When you create or join a machine to a site, logs at the Verbose level are written to <ArcGIS Server installation directory>\usr\logs\<machine name>\server. If the site creation or join fails, you can open the logs with a text editor to get more information about the problem.
Once the site creation or join is complete, the logs are moved to <ArcGIS Server installation drive>\arcgisserver\logs and the log level is set to Warning. If the ArcGIS Server account does not have permission to create or write to this folder, the site creation or join will fail. If you don't want to give the ArcGIS Server account permissions to create folders on your entire drive, you can manually create this folder in advance and grant the ArcGIS Server account permissions to write to it.