My system has developed a weird wireless problem. It is connected for a varying period of time (5 to 15 minutes), and then a message appears indicating "unable to connect to wireless network". Refreshing the available networks lists twice (the first will show no networks) gets me back online for another 5-15 minutes.

 

The weird thing is this: pandora.com, a free music service, plays indefinitely. On the premise that this keeps the connection, I opened another window and started browsing; however, the "unable to connect to wireless network" soon appeared. The music continued to play uninterrupted. The 'refresh available networks list' trick worked to allow browsing again. All the while the music played on...

 

Other Dell and non-Dell computers can connect wirelessly through this AP without the same issue. All configuration, passwords, broadcast channel, etc. have been rechecked. This has been a stable configuration for several years.

 

Setup: