I bought a Windows 7 Professional refurb laptop and have been pleased with it so far. However, it wouldn't read my Transcend 64gb USB key. I tried all of the ports. I tried updating the USB driver software from the HP support site. I tried forcing the drive letter when mounting. No joy.
The laptop would, however, read many other USB keys with no difficulty. That helped -- it indicated that it wasn't the USB ports or USB driver issue. Which was good, since I didn't really want to return the box. Usually I can fix software issues -- hardware issues on laptops are more difficult.
I found a few others who were having this problem with their HP ProBooks also. And it frustrated many of them. After much searching, I stumbled across this post: http://www.tomshardware.com/forum/62374-63-windows-unable-read-flash-drives
Sure enough, disabling "File Sanitation for HP Protect Tools" solved the problem. To do this, I searched for Services:
When Services Opened, I sorted by name by clicking the "Name" header.
I then double-clicked on HP File Protect. And disabled that thing with extreme prejudice. :-) Stop the service, and then also disable it on start up.
Then I inserted by Transcend 64 gb USB key and it came up cleanly. Stupid HP and their bloatware. Ugh. Good luck to you and I hope this helps!
