Hi Guys, I had the same problem, but since I have made a couple of changes, my scan now is always 100% complete, 31,476 songs in 3,208 albums taking 3min 59 secs.
I used to get the errors and a stopped scan the same as you are, my filing system was this, L drive/Music/ then the folders i.e Led Zeppelin then sub folders of each album by Led Zep. L:Music/Led Zeppelin/Houses of the Holy
Now, when my system used to terminate during a scan, I went to the name of the directory (Led Zeppelin) and found a music track inside the Led Zeppelin folder along with all of the album sub directories. I deleted or moved the file out of the parent directory and into another sub directory with other music files (if I wanted to keep it).
I re-ran the scan and it went past Led Zeppelin only to hang at another folder, again when I looked in here I found a stray track, so I moved this and voila, it went past on the next scan.
Conclusion (for me anyway) I checked that I had NO individual music files in directories on the way down to the final directory and now my system is perfect, this may not be the answer for all of you, I KNOW it fixed mine, so good luck with yours !!!!!
Kind regards, Nick