Accidental deletion of Registry entry supporting cameras

[MJL]

Hi.  I'll save you from the long story about how/why it happened but I've accidentally deleted one or more registry entries which control how windows detects and installs a camera when it's plugged in via a USB cable.  Short of rebuilding my computer, is there any way of restoring these entries.

I don't have a restore point or a registry back-up or any sort of sensible safety net 

Now when I plug in a camera, in the device manager it shows up in the unknown device type category and the device name is simply 'Still Image device' (or something like that.  I can't remember exactly but it's something generic like that).  It doesn't show up as a mass storage device in My Computer.  It doesn't show up in the scanners and cameras window and I can't run the Scanner and Camera installation wizard.

I'm at a loss.  I've already gone through the "remove hidden devices" clean-up in hopes that that might resolve things.  I've also tried removing my USP Root Hub devices and letting them reinstall.  This didn't' help either.

[techbeard]

Hi,

Have you tried doing an F8 boot and selecting Last Known Good Configuration?

All the best,
Karl

[Allan]

Do a repair install (boot to the XP CD and choose the second repair option).

[MJL]

Hi,

Have you tried doing an F8 boot and selecting Last Known Good Configuration?

All the best,
Karl

I haven't tried that.  I'll give it a whirl and see what happens.

[MJL]

Do a repair install (boot to the XP CD and choose the second repair option).

I'd thought about this but I'm concerned about making things worse...  I dual boot with Linux.  I fear that I may loose my GRUB boot loader.  I'd have to investigate how to get that back...

I'll give this a whirl as well

Thanks for the advice.

[MJL]

Ok.  So I tried using the Last Known Good Configuration.  This didn't work.  I think that this is because, apart from the problem with not recognizing cameras, Windows it's self is working fine.

Before I try the repair install from the installation CD - can anyone tell me.  Will I have to recreate my user accounts?  This is a family PC with each family member with their own account.  I understand from the literature I've read that the data will not be effected but does anyone know if the user accounts themselves will be removed.  Will the be there when the repair is finished or will I have to recreate their accounts and copy in all of their data?

[patio]

Repair Install of XP...

Done properly all your data will be intact including User accounts and profiles...

Done improperly ALL your data will be gone but you will have a fresh install of XP...

This is why i suggest reading it thoroughly and printing out a reference copy before starting...

PS...another safer approach before attempting this would be to go to Start/Run and type in sfc /scannow and hit Enter...
Have your XP CD handy as it will ask for it in most cases...
Let it finish and re-boot.
This may or may not restore the missing reg entries.

[Allan]

Repair Install of XP...

Done properly all your data will be intact including User accounts and profiles...

Done improperly ALL your data will be gone but you will have a fresh install of XP...

This is why i suggest reading it thoroughly and printing out a reference copy before starting...

PS...another safer approach before attempting this would be to go to Start/Run and type in sfc /scannow and hit Enter...
Have your XP CD handy as it will ask for it in most cases...
Let it finish and re-boot.
This may or may not restore the missing reg entries.

To the best of my knowledge system file checker does NOT effect registry entries, only system files.

[BC_Programmer]

how does one accidentally delete a Device key from deep within the HKEY_CURRENT_CONFIG key, anyway?

[Allan]

how does one accidentally delete a Device key from deep within the HKEY_CURRENT_CONFIG key, anyway?

Well you see there was this big gorilla...... 

[MJL]

how does one accidentally delete a Device key from deep within the HKEY_CURRENT_CONFIG key, anyway?

Well, since you asked...

It all started because my computer was booting/logging in very slowly.  I traced the problem to the WIA service.  It was hanging on startup.  As soon as I disabled the service my login was speedy quick.  So... I uninstalled all of my camera software (Canon XTI) and tried to re-install it.  The install hung part way through (don't know why).  When I tried to re-install the software it told me that it was already installed (because it as detecting registry entries) even though it wasn't.  There was on uninstall so I was between a rock and a hard place (so I thought at the time...).  Couldn't install the software and couldn't uninstall it.

The is where the foolishness started... I went into the registry looking for any entry which had the word "Canon" in it and simply started deleting.  It worked!  I was able to install the software... all was good... but... I plug in the camera and it doesn't show up.  The software doesn't know about it, it doesn't show up as a storage device and when I look in the device manager I see that it shows up in the unknown category as a digital still image device.

Pretty dumb eh?  No Registry backup (takes too long...), no restore point... takes up space...  Some day I'll learn.  My wife hates it when I do this.  Doh!

[MJL]

One more question regarding backing up user data. I have my computer configured like so;

C: Drive has only the OS and user profiles
D: Drive has all user data.
E: Drive has all application software
F: Drive is an odds and ends disk.  Music mostly
Z: Drive is is a small drive used exclusively for cache

Given that all of my user data is on a separate drive from my OS do I need to back it up?  There's a lot of data there.  I don't actually know how I'd do that apart from buying another drive...

[Allan]

Have you reset the WIA service to automatic or manual?
Did you try a repair install?

[MJL]

Have you reset the WIA service to automatic or manual?
Did you try a repair install?

The WIA service was set to automatic.  I set it to Manual but this didn't make a difference becuase the Canon service was calling it at start-up time and then it was failing so the effect was the same as having it set to automatic.

I haven't yet tried the repair install.  I'm at the step of backing up data I'm not prepared to loose.  If the repair install rebuilds my registry I think it will work.  If not I might be in fresh install teritory.  Ugh!  Done it before, can do it again.  It's just a lot of work...

[patio]

To the best of my knowledge system file checker does NOT effect registry entries, only system files.

That's true...but if it replaces a needed service a new registry entry is then created...