File Ownership Problems

I ran a major upgrade to some accounting software on my Win2KPro network (30 users), and since then, I've had problems with file rights and ownership with some programs on that server. One program, for example, was giving errors along the lines of "you don't have write permissions for this file, so I'm closing this program ". I looked at the properties for that file. SYSTEM was the only user listed in the rights window and all boxes were unchecked. Clicked Advanced, it gave a warning that I don't own the file, but can take ownership. Under the Ownership tab, the current owner was "Unable to display owner ". I took ownership, gave the Everyone group full rights and problem solved. But I keep finding files like this.

Do this sound virus-esque? Anybody run across this before?

 

Instead of changing permissions for each file individually, change permissions for a directory that contains all the files and propagate the permissions to all daughter direcxtories and files.