BE 3600 / 3600 R2 came up on Win server 2008 R2, however this opeating system is harden and is customized to make it more secured.
By design, user is unable to perform an RDP session to Windows on Appliance. When an attempt is made to RDP in the appliance, it will accept credentials and immediately log off again by itself.
To get it enabled, we normally need to enable it using certain powershell commands as mentioned in the document below :
Basic Requirements on the client machine :