A long post, but this info is HOT... :knock: I have searched for days and I finally found help. I have reinstalled USB drivers, deleted USB hubs and devices in Device Manager and let windows XP sp2 reupdate them on bootup (as you suggested at USBMan, a "safe" boot delete of USB devices). I have bought three thumb drives from Lexar and Centon. They are not recognized by windows. I have read dozens of posts to forums at Centon, USB Man, Microsoft,etc. and tried all of the suggestions that I could find. Ghost devices conflicts and how to show/delete them, bios updates, Microsoft USB Flash drive manager, Administrative Tools, COmptuter Management in Control Panel, reassigning device letters, double checking/installing the usb.inf file,... trying to reinstall drivers....I even clean installed windows xp and downloaded all updates to SP2...I give up. Nothing works. I can plug in a USB camera, joystick, gamepad, MP3 player, etc. of well known or just cheap stuff and they are INSTANTLY recognized by the same USB port (I have 8) that I try to use on the 1gig data stick flash drive, with no loss of power issue that I can see... The red light works, but all I get is "this USB device attached to this computer has malfunctioned or is not recognized by windows" The data stick works on other computers (so did the other two that I returned, thinking the sticks were bad...)but not on my machine. I really need to use a flash drive and surely there is an answer to why one particular computer will not "see" this datastick and others do... floppies are not an option. All my other USB devices work perfectly, but none of the plugged in flash drives.... Lexar was no help, Centon tried, microsoft was no help and I have exhausted your forum...and several others. [[ RESPONSE]] (this helped a little) How is the device connected? through an external hub? (if so, powered or non-powered?) direct to front USB port? direct to rear USB port? What is the manufacturer and model of your computer? if generic, please specify your motherboard manufacturer and model. For the Windows re-install that you did, please specify the source CD. Was it a computer manufacturer provided restore CD? Was it a full version of XP? What is the error code for "this USB device attached to this computer has malfunctioned or is not recognized by windows"? ]] ANSWER/SOLUTION Connect in the front from an internal USB Flash drive as well as extra front USB 2.0 ports and tried in the back of the computer with USB 2.0 on motherboard. Asus P5GD2 Deluxe w/ 3.4 intel and 1 gig ram. The install was from a full factory CD. There was no error code...just a little window pop up that said "USB device not detected", etc. HOWEVER. . . ! While waiting for a response from you guys I was able to go into the BIOS Advanced USB section and reduce the number of USB's from 8 to 6. This disabled my Flash Drive, but the memory stick was Recognized in the front port and the back port! So I think it was a power issue. The only other think I changed in the BIOS was "FDD" = "force hard drive" for those ports. I plugged in a joystick immediately after checking the memory stick and it worked as well. Thanx...hope this saves somebody else a full weekend of agony...for something so simple.