Vista reports in the System Event Log EventID 20001 with the content "Driver
Management concluded the process to install driver NULL Driver for Device
Instance ID USB\VID_0FCA&PID_0001\5&6B8F2A6&1 with the following status:
3758096899"

What Vista did was re-associate ALL of my external USB storage devices with
the NULL Driver making it impossible for me to use my external USB connected
drives, including my ReadyBoost drive which was in operation at this time
(this EventID 20001 was immediately followed by EventID 51 messages
concerning the system's ability to write to the ReadyBoost drive).

The only extraneous process running at the time was Windows Defender which
was doing a scan of the system at the time.

Associated with the EventID 20001 is an NTFS Event 137 claiming that "The
default transaction resource manager on volume Z: (the ReadyBoost drive)
encountered a non-retryable error and could not start."

The USB devices in question continue to work on other PCs running Windows XP
SP2, Server 2K3 R2 and Windows 2000 SP4.

This event causes all USB storage devices, including newly purchased ones,
to fail as "Unrecognized Devices" upon installation. Forcing the installation
of the USBSTOR.SYS driver with these devices does not fix the situation.

It is also worth noting that when the devices are connected they appear in
HKLM\SYSTEM\CurrentControlSet\Enum\USB as VID_0000&PID_0000 while the
properties of one of the problem devices (as extracted from Device Manager)
reports the "Matching device id" as "VID_04BB$PID_0301"

I have attempted to delete the HKLM key in question but Vista reports that
neither the Owner nor the Administrator have rights to change settings (in
fact Owner and Administrator don't have rights to affect changes on anything
in HKLM\SYSTEM\CurrentControlSet\Enum)

I am thinking of creating a script assigned to run at startup if I can
ensure that it will run with SYSTEM credentials so that I can eliminate the
NULL Driver now associated with all the USBSTOR.SYS devices.

Comments, help or anecdotes of similar experiences would be appreciated.

Don't know if you are still looking for a solution to this problem, but
it took me about a month to have this one solved. As I did not find a
single solution on the internet, I decided to post mine here, in the
hope that other people can solve their problem with my post.

I am still not shure what caused the problem, nor what of the several
actions I took this evening solved it, so I post them all, in the hope
that someone can narrow them down to one action.

It seemed that usb storage devices intered into my machine worked fine,
if they had been entered already before a certain (unknown) date, new
devices were assigned to the null driver.

I was expecting that one of the oemxxx.inf files in my c:\windows\inf
folder was causing this strange behavier as I have been evaluating
several usb devices for a project of mine. As they were able to get
inthere, I assumed that if they were missing, I would be able to replace
them. So I created an empty folder on my desktop and started to go
through my oemxxx.inf files from high numbers to low and moved them into
the empty folder together with the coresponding .pnf file till I had
only files that came with the original install (refering to lenovo in my
case). I also moved the unknown.inf and .pnf into the folder. I was
thinking to give it a reboot that way, and than I noticed that the file
usbstor.inf was missing. I did a search on my disk and found 4 copies.
one (the oldest) was about 27k in size, the 3 others were about 28k,
same size and date. I decided to copy one of these into the
c:\windows\inf. Then I was scared that my windows repair system would
remove it again. So I pulled out the powerplug and battery.

When I restarted the machine, it offered me to start in safe mode. I
decided to choose this option. After the safe mode boot, the usbstor.inf
was still there, without .pnf.

I did a normal reboot (from the start menu) and started in normal mode.
still had te usbstor.inf file in the c:\windows\inf folder and still no
.pnf file. I inserted an old usb stick and it worked fine as before. No
difference to the files. Than I entered a new usb stick that did not
work till about one hour ago. Entering set off the PnP system, the .pnf
file was created and a new drive letter was assigned. The stick works
now fine.

I hope someone narrows this down, if not, I hope that the same
procedure works for you.


--
kmeuleman