Entering a shorter string usually corrects the problem. However, if you need to enter a numeric value larger than the field ...

Entering a shorter string usually corrects the problem.  However, if you need to enter a numeric value larger than the field is designed to hold, you must either change the bounds of the numeric field or change its data type (for example changing the data type from an integer to a long). To change a field size in a linked data source, you must open the program that controls the design of the table and make the necessary changes to the field schema.  If you do not own the data source you probably cannot change the field schema.  After the field size is updated in the linked data source, your Access table will reflect the changes.