I have Windows XP SP2 installed. Currently I got myself an USB bluetooth dongle. The manufacturer had provided with BlueSoleil installation CD. After installation of BlueSoleil I restarted my PC and connected my dongle to the USB port. The follwing message appeared. "One of the USB devices attached to this computer has malfunctioned and windows doesnot recognize it. The location of the device is shown in bold type". In USB root hub (3 ports)one port says unknown device(bold) and other two ports say unused port. In recommendation it says "Try reconnecting the device. If windows still doesnot recognize it replace the device.". When I double click on the highlighted unknown device item following message appears under device status. "No driver are installed for this device". Under device usage the device is enabled. Device tpe says Universal Serial Bus Controllers. I had replaced the device with new ones twice, but it does not work. I tried it in some other PCs but the same message comes there too. I uninstalled BluSoleil and installed WIDCOMM but the same thing happens. Somewhere I got to know that changing bth.inf in windows folder to bth.bak will solve the problem. But that didn't work either. What do I do now?