Problem:   

 IT support staff require an easy method to support remote staff.  Microsoft Lync provides remote desktop viewing but it does not provide Administrative assistance.  Third-party solutions exist but require subscriptions, etc. 

Solution:

 Enable Windows Remote Assistance (RA).  Windows Remote Assistance has improved from the Vista days when it was first released.  When properly enabled, IT staff can initiate an unsolicited RA session to any workstation on the domain; the entire process is simple and intuitive.

Enable RA:

   First, create a "Remote Assistance" GPO within Group Policy Management. Within the GPO there should be 2 policies enabled:

    First GPO:

Computer Configuration\Administrative Templates\Network\Network Connections\Windows Firewall\Domain Profile\Windows Firewall\Define inbound program exceptions:  enabled.

    Add Exceptions to GPO Attribute:

%WINDIR%\SYSTEM32\Sessmgr.exe:*:Enabled:Remote Assistance
%WINDIR%\PCHealth\HelpCtr\Binaries\Helpsvc.exe:*:Enabled:Offer Remote Assistance
%WINDIR%\PCHealth\HelpCtr\Binaries\Helpctr.exe:*:Enabled:Remote Assistance – Windows Messenger and Voice

   Second GPO:

Computer Configuration\Administrative Templates\System\Remote Assistance\Configure Offer Remote Assistance:  enabled.

    Create RA Security Group:

Specify AD security group or users to permit remote control of domain workstations.

Assign the RA GPO to workstations OU.

Once the RA policy has propagated the workstations are ready for administrative remote assistance.

Managing RA: 

   Providing remote desktop support is a simple process.  IT staff can run the following command to start the remote session:
Msra.exe /offerRA computer-name
   The Msra command works with both hostname (i.e. computer name) or IP address.  Msra starts the remote session with an end-user request.  The end-user receives a pop-up window that requests permission to start the RA session.

That's It!

References:

http://technet.microsoft.com/en-us/magazine/ff356868.aspx

Active Directory Network Administration RDP Windows Server