Empty text file - full disk
This morning I discovered my .vbs script file was 0Kb. The other day I made a small change and saved it. The disk drive that I saved it to was full (I learned that this morning also). Could the full disk drive cause me to lose all my text when I saved the changes?
If the disk was the one containing your Windows system, I think the whole operating system may have become unstable when the disk filled up - possibly aborting NP++. It is not a good idea to run with nearly full disks, but of course a program that gets stuck in a loop can easily fill a disk.