problems with USB Mass Storage driver in XP

[vphreeze]

i am having issues with trying to install a USB microSD card reader on my laptop. its coming up with the New Hardware dialog, but when i tell it to search automatically, it shows that it recognizes it as USB Mass Storage, then it says Cannot Install this Hardware and "cannot find the necessary software".

i just did a clean install of XP Pro last week, and my 100gb external USB hard drive, my USB hub, MSC mp3 player, and a thumbdrive all were installed within the first day or two and all work fine. now i try to plug this in and i get nothing. i have also tried another microSD and a plain SD card reader and was met with the same results. all of those readers were completely plug and play on the old copy of XP Pro. i should probably also mention that the old installation of XP had a lot of stuff stripped out through nLite, and this one had nothing new taken out, but a lot of stuff added back in. i have verified that the card readers work on other computers.

after doing some research, i saw some people saying it might be caused by manual drive letter assignments, so i changed all those to the last half of the alphabet but it didnt work. i tried replacing the USBSTOR.sys and USBSTOR.inf with fresh copies, and no change. i also tried following some instructions that were given to someone with a smilar problem by Microsoft that involved deleting some VID registry entries and hidden entries in the Device Manager...but after reboot, i couldn't reinstall any of the stuff that worked before, not even my trackball mouse (same issue with it recognizing stuff but "cannot find the necessary software"). i restored a System Restore Point from a couple days ago and everything went back to working fine except i still couldn't install the card reader.

any ideas? are there other files besides the 2 USBSTOR files i mentioned that i should check on or replace?