Increase MaxLocks Permanently in Registry
1. Click 'Start,' then type 'regedit' (without quotes) in the search box. Press the 'Enter' key.
2. Click the 'Computer' link in the left windowpane. Navigate to the 'HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Jet\4.0\Engines\Jet 4.0' value entry' if running Access versions 97, 2000, 2002 or 2003. If Running Access 2007 or 2010, navigate to the 'HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Office\12.0\Access Connectivity Engine\Engines\ACE' entry.

3. Double-click the 'MaxLocksPerFile' entry on the right side of the window. Change the number in the 'Value Data' field to a higher value, and then click 'OK.' By default, Windows uses a 'MaxFileLocksPerFile' value of 9500. Change the value sufficient to handle the maximum number of rows in the largest data table. Leave room for growth in the database as well. For example, if the largest table in your database has 100,000 records, set the value to at least 200,000 to accommodate new data entry.
4. Close the Registry Editor.
Change Max Locks Temporarily in Code
5. Launch Microsoft Access and open the database causing the Max Lock errors.
6. Click 'Database Tools' on the menu or ribbon bar, then the 'Visual Basic' button. The Visual Basic for Applications window opens.
7. Right-click the name of the database in the 'Project' pane. Click 'Insert,' then 'Module' on the pop-up menu.
8. Enter the following code under the 'Option Compare Database' label:DAO.DBEngine.SetOption dbmaxlocksperfile,200000Change '200000' to the desired number of Max Locks, and then save your work. Access increases the number of max file locks to the value you entered. Once you exit your application, the setting reverts to the original value in the registry.