PC connects randomly to Remote desktop

Ok, I have a deputy that has a laptop in his car that we have setup a remote desktop shortcut on his desktop to a criminal program on one of our servers. His pc will on most occasions not connect, but every now and then it connects. We have checked and double checked the settings on his laptop as well as the server. He is setup completelhy the same way as all of the other deputies that have these laptops in their cars.
Any help in this matter will be greatly appreciated.

 

Nothing in Event Viewer on either the pc or server. When we try and connect we get a message saying that it timed out and try again later. He is the only deputy that cannot connect. We have tried it with his logon as well as my logon. This is an XP Pro SP3 machine. It is a General Dynamics GO Book XR-1.

 

We believe we have fixed it, but not sure why it only affected this laptop and one other desktop pc. We had issues with AVG on this server before and as a hunch we uninstalled it from the server and now both the laptop and the desktop can connect perfectly to RDP. I do not know why it chose these 2 systems and not the other 50 that connect to this server VIA RDP, but they connect. Now we have to figure out what to do with the AVG.
Thanks for the help.