XenServer Tools not registering with XenCenter Host
Problem: Windows 7 Installed XENTools – but after multiple attempts and installations its still not registered in XenCenter 6.0
Also ensure the RPC Service are running.
Solution: Install .net Framework 4.0 FULL (including extended features) – http://www.microsoft.com/download/en/details.aspx?id=17851
MSCONFIG can play a part in this also – in my instance i had to restart all services (set MCSONFIG to normal) and then restop a bunch of garbage services to get this working even AFTER installing the .NET 4.0 extended framework
References: http://support.citrix.com/article/CTX130986