Using Kubuntu 11.10. Sony Vaio computer. Network controller: Intel Corporation WiFi Link 5100.

If I connect to a wireless network, and the signal drops, then I am unable to connect to any network without a reboot. I can assure that the issue has nothing to do with the computer going to sleep, as I have experienced the above while using my computer continuously.

Here is exactly what happens:

1. Connect to network (at University, where the connection is not so great).

2. The connection is broken

3. There are three other possible networks available, but none of them can be connected to. I have tried off and on sometimes for hours.

4. I am always able to reestablish a connection after a reboot.

I can only think of two explanations. The first is that a temp file is corrupted when the internet connection is abruptly dropped. The second is that my computer actually corrupts something before the loss of internet connection, which causes the loss in signal, and inability to reconnect. However, I am not confident that my explanations are complete, nor do I have any idea how to test these things.