I had a PC that had run fine with this wireless adapter (WUSB54G v4)for more than a year. One day though, Windows ran an update and it stopped working. I figured the issue was with the adapter and replaced it with something that I got from newegg on sale for $10. A few months later though, I decided to try the WUSB54G on another computer. This time, an HP D530. It worked fine for months and again one day blue screened. I finally decided to do some reading and found that the problem was in the RAlink drivers. The problem is this file: RT2500USB.INF. It is located in %windows root%system32drivers. The one installed with the linksys download is no good. You need to go over to RAlink’s site and find the RT2500USB driver file for your OS and version. You then need to download that file and extract it with something like winrar and find rt2500usb.sys. Copy that file into the directory mentioned before (overwriting the old file) and you should be in business.
Why linksys would have allowed this to happen without a patch since 2005 is beyond me, but I’m guessing its just to get you to go buy a new Wireless-N adapter.