Well, about my system. WindowsXP Home, PIII, 733MH, 384MB Ram. wmp ver. 8 I think (whatever version comes with xp). I'm thinking of formating my HD again (I do that once in a while), and get rid of some of the zillion prgs I have installed, and never use. See what happens after that. Thanks for taking the time to look into this. I appreciate all your help. Edit Forgot to mention. There were lots of automatic updates to xp, and some of them probably went into wmp too. Anyway, I've been using avisynth for a long time, even before I new it and as a matter of fact, I could never open version() in wmp. (at first I thought it didn't work). But if I do StackVertical(version,version), plays fine