- 1). Open Microsoft Access 2007. Click the round button in the upper, left of the screen containing the Windows log and choose "Open." A pop-up box will appear. Navigate to the location of your database file, click on it and click "Open."
- 2). Click on the "Design View" tab in the upper menu choices along the top of the screen. Click on the "Table" window to display a listing of your database categories. Your current primary key is displayed with a picture of a "key" to the left of it.
- 3). Click on your primary key category. Navigate to the "Design" tab along the top of the screen and press the "Primary Key" icon in the upper, left-hand corner. This removes the current primary key assignment.
- 4). Navigate back down to the listing of database categories. Click on the blank box to the left of the row you want the new primary key to be. Click the "Primary Key" icon above to update your primary key.
- 5). Navigate back to the top of the screen and click on the round button in the upper, left-hand corner with the Windows logo and choose "Save As." Make sure your file is still located in the correct place within the new pop-up window and click "Save."
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