I'm betting on the newline as a previous poster said.

Two nits. First, you don't have to convert c:/windows/mycrap to c:\\windows\\mycrap. Forward slashes are just fine. In fact, they're actually *better* because you don't ever have to worry about counting backslashes, miscounting, getting an odd number of them, and then having all kinds of weird escaping issues. And they're Unix compatibile.

Second nit, the quotes in the opendir aren't necessary. opendir(DIR, $dir) || warn "opendir $dir: $!" is just peachy.