FAQ 2114
Access Database: Max number of locks exceeded

The internal column count that Microsoft Access uses to track the number of fields in the table has reached 255. To free the internal column count for deleted fields or for fields whose properties you modify, do one of the following: Compact the database. On the Tools menu, point to Database Utilities, and then click Compact and Repair Database. -or- Create a new copy of the table. To do so, follow these steps: 1.Make note of any relationships with the table. 2.Select the table. 3.On the File menu, click Save As. 4.In the Save Table 'table name' To box, type a new name. Click OK. 5.Select the same table that you selected in step 2, and then press DELETE. 6.Rename the table that you saved in step 3 to the original table name. 7.Re-establish any relationships with the new table.