If its happening every ten or so minutes, it might be your laptop turning off your network adaptor to save power. That would explain why the trouble shooter turning it back on fixes your problem. If you haven't already done so, go to the Power Management tab in the Configuration of your adapter and uncheck the box that says "Allow the computer to turn off this device to save power".
When this happened to me (connected but Limited), the network troubleshooter said it was unable to get an IP address. To fix it, I temporarily turned of my Avast Internet Security firewall, reset the wireless adapter by putting it in and out of flight mode, ran the troubleshooter again and confirmed I could now get an IP address, and then re-enabled the firewall. I haven't had any problems since.