Finally got reply from Folder Lock people -

"
Load your computer in Safe Mode or in Dos Mode (this can be done by loading your computer with the help of a bootable disk, floppy or a bootable CD) and
then delete the file called 'windrvNT.sys' from your Windows system folder, which is Windows\System or Windows\System32.

Once you've deleted this file, boot the computer normally and you can use the computer without any problem with all your files recovered.
"
2 questions - how do I boot into "Safe Mode" and will the file they mention deleting - rebuild itself?

OBTW I used the event viewer and it specified "Bug Check" which I assume is a program exception.

Tom