This is kinda interesting... I'm having a problem in Access 2000 with a master child relationship on a subform. Currently, my master field is set as a combo box on the main form, and that works fine, but if you try to change it more than like twice, it freezes up, gives me a GPF and then kicks me out. It works fine with Access XP and also Access 2003, but Access 2000 doesn't like it. Has anyone ever heard of anything like this? Furthermore, does anyone know what I can do to keep it from happening, aside from upgrading all my machines in the office? By the way, this is an Access Project File in 2000 format, and it's using a MS SQL Server backend. It happens on every single Access 2000 machine that I have, but not my laptop, which is running 2003. Any help would be greatly appreciated. Thanks!