Repeated Unexpected Shutdown BC Code 124

Find the drivers for the DVD drive.
To do this, open Device Manager, right click on the DVD drive, select Properties, select Drive tab, select Driver details
See if PxHlpa64.sys is listed.

If it is, then we'll have to try disabling it to see if that works.
To do that:
- create another restore point
- open Autoruns (you used it when creating the initial reports)
- search for PxHlpa64.sys - and disable each entry by removing the checkmark from the left hand side of the entry.
- remember which one's you changed, just in case you have to change them back manually.
- reboot and see if that fixes things.
- check Driver Details again (after reboot) to see if PxHlpa64.sys is still listed
- if not, rename it to PxHlpa64.BAD
- if it is, post back and we'll see what else we can do.

We're looking at Roxio, Sonic, Music Match Jukebox, or WinAmp
We're not looking at Nero - it doesn't use it.

At the bottom is (IMO) the most likely fix (the one with the "FixIt")

Here's an excellent article about removing this stuff: Uninstalling all files for Sonic Burning engine? - Winamp Forums
First, search your system for pxsetup.exe.
Then open a elevated (Run as administrator) Command Prompt and type:
the full path to pxsetup\pxsetup.exe /uninstall
See if that removes it.
If not, then follow the rest of the steps in the article

Nifty free tool here for getting more detail: busTRACE Filter Driver Load Order

Another way to remove the driver (actually it's filter entry in the registry): http://djlizard.net/2007/04/30/230/
Made for XP but should work with Win7. Make a system restore point just in case.

Simplest solution:
- set restore point
- rename pxhelp file
- make fixes in autoruns and in registry
- reboot and ensure that there's no CD drive showing
- run the "FixIt" in this KB article: Your CD drive or DVD drive is missing or is not recognized by Windows or other programs
(got it from this post: Upper Lower Filters in XP Registry )

That's the purpose of the System Restore point - if you "blunder", then you'll be able to fix it with System Restore! :0)

On second thought, maybe just set restore point, rename to .BAD and then run FixIt
Next try would be to set restore point, rename to .BAD, disable all in Autoruns, then run FixIt
Next try would be set restore point, rename to .BAD, disable all in Autoruns, then go blundering around in the registry, then run FixIt

No problem with being reticent to muck about in the registry.
But, it's OK if you can:
- make a copy (with System Restore)
- and know how to revert back (using System Restore from the System Repair Disk)