BSOD on Windows 7 Pro - pssnap.sys - PAGE_FAULT_IN_NONPAGED_AREA - Macrium Reflect

Question

I recently ran Windows Update on Windows 7 Professional, as I do every few weeks. Everything seemed to go OK, until I restarted and after the animated flag logo formed up, I got a flash of a blue screen and an immediate restart.

Using F8 to prevent restarts, I was able to read the screen...

A problem has been detected and Windows has been shut down to prevent damage to your computer.

pssnap.sys

PAGE_FAULT_IN_NONPAGED_AREA

A quick Google shows this is caused by the interaction of Macrium Reflect (back-up software) and a Windows fix for SPECTRE.

I didn't think I still had Macrium installed, so it appears to have left behind the pssnap.sys, which is used at start-up time. Macrium have issued a fix which removes this file from start-up and new versions of the software no longer install it as a start up service...

https://knowledgebase.macrium.com/display/KNOW7/Windows+7+32+bit+BSOD+after+MS+Windows+Update

All well and good, but the fix doesn't work for me :-(

The fix involves booting from a Macrium-customised Windows PE and then running their removesnap.exe (downloaded onto a USB stick) which I think alters the registry to prevent the c:\windows\system32\drivers\pssnap.sys from running.

It tells me it has run successfully, shows the path of the registry entry and everything. But when I reboot, the BSOD is still there.

I have tried renaming pssnap.sys to pssnap.old. But when I reboot I still get the BSOD (but without the reference to pssnap.sys and the PAGE_FAULT_IN_NONPAGED_AREA).

I have also tried installing a later version of pssnap.sys (by getting a newer version of Reflect and putting it on another boot partition and copying this newer pssnap.sys over the older one.) I still get the error.

So I was wondering whether it's not working for me because I have a dual-boot (well multi-boot machine)? I have an SSD with Win 7 and Win 10 plus a HDD with the old versions of Win 7 and Win 10 which were copied to the SSD.

Is it possible that the removesnap.exe doesn't know which installation to work on?

I have no system restore points and neither Windows PE or the standard Windows 7 rescue is able to repair the system. Booting in Safe Mode still gives the BSOD. And Last Know Good doesn't work either. So I'm truly stuck.

My only other option is to copy again my Windows 7 HDD over to the SSD and put up with the fact it's out of date.

Any/all ideas gratefully received!