I have looked at other posts but not found an answer to my problem. I have purchased a PQI USB2.0 256Mb Cool Drive (Flash Drive). It works fine on my laptop (XP Pro) and on one of my PC's (XP Home, SP1), but not on my main PC (XP Home, SP1). When I plug the CoolDrive in, it is recognised by my PC, and appears as both a USB Mass Storage Device and a Disk Drive in Device Manager. When I check the properties of USB Mass Storage Device, it appears to be working OK. When I check the properties of Disk Drive,my PC hangs up. The CoolDrive appears in Explorer as Drive G:. However it causes Explorer to freeze up. If I remove the drive then Explorer works OK again. I have tried to change the drive letter from G: to something else using a suggestion posted elsewhere on this forum. However when I try and do this with the Cool Drive plugged in, it causes my PC to hang up. Unplug the Drive and everything is OK again. I have tried to uninstall the driver using Device Manager (USB Mass Storage Device), once again it just hangs up. All help appreciated. I've tried everything I can think of. I have SP1 installed, and other USB 2.0 devices (such as an external USB2 HDD) work fine.

You said: I have tried to uninstall the driver using Device Manager (USB Mass Storage Device), once again it just hangs up. Just uninstall the entire controller and reboot. Windows will reinstall w/ default driver. This can happen when removing a locked device. The trouble with the world is that the stupid are cocksure and the intelligent are full of doubt--Bertrand Russell

Scout, Which Controller should I delete. I see the following: * Generic USB Hub * Intel PCI to USB Enhanced Host Controller * Intel(R) 82801DB/DBM USB Universal Host Controller -24C2 * Intel(R) 82801DB/DBM USB Universal Host Controller -24C4 * Intel(R) 82801DB/DBM USB Universal Host Controller -24C7 * USB 2.0 Root Hub * USB Composite Device * USB Root Hub * USB Root Hub * USB Root Hub plus USB Mass Storage Device (when the flash drive is installed). Many Thanks

Sometimes a PC's USB ports simply cannot supply sufficient power to devices giving similar symptoms to those you are experiencing. There is clearly nothing wrong with your flash drive so this may be your problem. I have seen this several times with external USB hard drives but not with a flash drive I must admit. If your USB ports are on the Motherboard you may have to resort to an addon PCI card.

I have seen this problem many times. How many usb devices are u using? I have a flash drive that that used to work fine when it was the only usb device, but when i pluged my printer and digital cam back in it hanged. I only had a 250w powersuply so i upgraded to a 450w and it solved the problem. I think that ur comp may just not have enough power to run that usb device. Those devices requier alot of power to right and read dada fast. Try unpluging other devices and if u have to upgrade ur PS. There not to expencive...tigerdirect.com sells some 4 like 30 bucks.

You have a few. You can try two ways. In device manager, disable them one by one until you find the right one. You just re-enable if it isn't the one. The other way is to uninstall all of them and go for it. The trouble with the world is that the stupid are cocksure and the intelligent are full of doubt--Bertrand Russell

Thanks for the suggestions, alas.... I have tried disconnecting all other USB devices - it still does not work. I have tried each of my 4 USB ports - no change. I have tried uninstalling all of the USB controllers in Device Manager, allowing them to reinstall - it still doesn't work. Since it works OK on my other PC's, but not on my main PC, it certainly seems to be a problem with my main PC OS or Hardware. Any other suggestions gratefully appreciated.