This error occurs when a user logs into RWA on SBS 2011 and the Computers gadget is unable to determine which, if any, computers the user has permission to access remotely. In my case the user permissions were set correctly in the SBS console and she was to have access to one computer.
While researching the solution to this problem we found the following TechNet Forum solution: http://social.technet.microsoft.com/Forums/en-US/smallbusinessserver/thread/386a0764-5623-4b0f-83b9-d442fdcdbb1b
It appeared to be a correct solution for the problem but the posted answer was a bit obscure to follow. Hopefully this is clearer.
- In Active Directory Users and Computers, select View and pick Advanced Features. This will enable you to see the security settings for your AD objects.
- Browse down to the SBS Users OU and note the permission setting for Authenticated Users is Read. If you press the Advanced button here you will see that the permission is for this object only.
- Brower down to the user having the problem with the Computer gadget. View the Security tab and note that Authenticated Users does not have any permission here.
- In the above article, Microsoft CSS reported this as being the problem.
Go back to the Security tab of the SBSUsers OU. Press the Advanced button.
Browser down to Authenticated Users and Press Edit. Change the Apply to, to Third object and all descendant objects
Close any sessions you might have open in RWA for that user. Then login as that person and the gadget will now be working.