I have been experiencing this error on certain workstations running W2K and FileMaker Pro 5v3 and 5.5v2. As soon as the user attempts to run FM they get a Windows error stating that: The instruction at "xxxxxxxxxxx" referenced memory at "xxxxxxxxxxxx". The memory could not be "read". Click on OK to terminate the program. I have done some web searches, and I have found incidences of this error dating back to 1998...but no solutions. Has anyone else experienced this issue? I believe it has something to do with file permissions, since I can run the app fine as a local or domain user with Admin rights...but the other users with restricted access cannot. Note that this problem just "started" with no changes done on our end. One day it worked, the next this error started.