Help! I have run into a rather odd problem in Windows XP Pro where after
a badly failed installation of an HP 5300C USB scanner the system has
been left in a state where I cannot run the Add Hardware Wizard at all.

(This scanner has always given me trouble. My old PC would only boot
provided that power was applied to the scanner after it passed the point
where it scanned the SCSI bus. The new one won't boot with it at all.)

The main sequence of events was install driver software. Reboot to
complete installation with the scanner plugged in. Unfortunately with
this particular scanner plugged in my new computer totally fails to
boot. Stone dead - not even a screen flicker from the ROM BIOS. Somewhat
alarming!

So the final stage is incomplete and a hardware installation is still
"in progress". I could see their HP Precision Scan "setup.exe" program
still loitering in the running process list afterwards.

There is an outside possibility that the damage was done by the previous
h/w install (a USB card reader) and the HP tripped up over it. I can't
unwind far enough back to test this. The USB card reader works fine, as
does a printer.

I have tried unwinding the registry, uninstalling all of the HP driver
software. Deleting every last trace of their software but still I get
the error report:

"Cannot Run Two Device Installations!

You can only install one device at a time. Another device installation
is underway, when it is finished you can try this wizard again."

OK. The install never finished so the hardware install wizard is on
strike.

How can I find out what it thinks is being installed?
How do I manually reset or trick it back into working?

I didn't spot anything obvious on the WinXP support KB.

It is rather frustrating not to be able to add new hardware to the PC! I
have something none Plug&Pray to install so I need to get the hardware
wizard working or alternatively find a safe manual workaround.

Thanks for any tips or pointers to resolving this problem.

Regards,
--
Martin Brown

In message <aPNYuhCmG$(E-Mail Removed)>, Martin Brown
<|||newspam|||@nezumi.demon.co.uk> writes

I know it is rude to follow up my own post. But here is a bit more info
and a final request for help before I give up and trash the OS with a
new working copy. (Until the next time the Add Hardware Wizard
self-immolates)

>Help! I have run into a rather odd problem in Windows XP Pro where
>after a badly failed installation of an HP 5300C USB scanner the system
>has been left in a state where I cannot run the Add Hardware Wizard at
>all.

>I have tried unwinding the registry, uninstalling all of the HP driver
>software. Deleting every last trace of their software but still I get
>the error report:
>
>"Cannot Run Two Device Installations!
>
>You can only install one device at a time. Another device installation
>is underway, when it is finished you can try this wizard again."
>
>OK. The install never finished so the hardware install wizard is on
>strike.
>
>How can I find out what it thinks is being installed?
>How do I manually reset or trick it back into working?
>
>I didn't spot anything obvious on the WinXP support KB.

And the only thread I found mentioning this problem recommended a
registry tool that didn't make any noticeable improvement either.

I have found that the registry key for hdwwiz.cpl of 0xffffffff looks
suspect, but changing it to a few more likely small values did not help


Please can someone confirm for me the correct value for the following
key on a working XP system ?

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Control
Panel\Extended Properties\{random_hex_machine_ID} 2

%SystemRoot%\system32\hdwwiz.cpl REG_DW 0xffffffff (4292967295)

I would bet the right value on a good system is less than 10, but having
tried 0 through 4 without success I suspect that there is another hidden
key somewhere. It continues to refuse to run. Not good

Regards,
--
Martin Brown

My value is 4292967295