I recently switched from Access 2.0 to Access 2000. My entire database runs fine except for a certain form/subform. I have a combo box at the top of the form where I can select a serial number for a given unit. Once selected, the subform produces a grid of results of utilizations for the unit, arranged in chronological order. Post install, I select a serial number, hit Enter, and the grid does not change. Any suggestions? Is this a Link Child/Link Master field problem? Thank you in advance.