Hi Graeme. Thanks for the reply, and I experimented further. If I put something new in the text box, it does indeed show up the next time. But if I just clear the box, then the previous non-blank value shows up the next time. I'd like the default to be blank, since I don't normally want to exclude anything. Of course, now that you've shown me what's happening, I could put some nonsense value there that will not actually exclude anything, but that's just a workaround.
I also tried (after backing it up) carefully removing the old values from vrestore.slk with another editor. That did the trick, but of course as soon as I ever need to exclude some filespec again, I'm in the same situation. That is, having the most recent value be "no exclusions" doesn't seem to stick, but the others do. I'm going to try it one more time, since it's possible that years of modification had gotten my vrestore.slk file into some kind of loop.