xps 18 windows 8.1 wireless problems

My client purchased a Dell XPS 18 running Windows 8.1 from Best Buy. I recommended he get the Geek Squad support which he did. The problem with this computer system is that the wireless drops out frequently. It uses a DSL modem with a local phone company called CenturyLink. The Geek Squad rep came by to install a Belkin N150 wireless adapter to remedy the problem over a week ago. Yesterday we were downloading the Microsoft Office and after 30 minutes at 61% done the wireless dropped out. There was a message saying that the adapter had been "disabled". I checked all the settings but was not able to discover much. We left the system on for over 9 hours to see if the download just might finish but it did not. The client is getting rather annoyed, as he is elderly and wants things to just work after spending quite a bit of money.