ACC: Cannot Change Some Properties of Attached Tables

• Microsoft Access versions 2.0, 7.0, 97

SYMPTOMS

Novice: Requires knowledge of the user interface on single-user computers.

You cannot change engine-enforced properties such as FieldSize, DefaultValue, ValidationRule, ValidationText, Required, or AllowZeroLength on linked (attached) tables. When you open the linked table in Design view, the following warning is displayed:

   In Microsoft Access 97:

      Table 'tablename' is a linked Table with some properties that
      can't be modified. Do you want to open it anyway?

   In Microsoft Access 7.0:

      Table 'tablename' is a Linked Table. Some properties cannot be
      modified. Open it anyway?

   In Microsoft Access version 2.0:

      Table 'tablename' is an attached table. Some properties can't be
      modified. Open it anyway?

   In Microsoft Access 97:

      This property cannot be modified in linked tables.

      NOTE: Microsoft Access 97 will still allow you to save the table.
      However, the change will not be saved.

   In Microsoft Access 7.0:

      Microsoft Access cannot save changes to properties of linked
      tables.

   In Microsoft Access 2.0:

      This property cannot be modified in attached tables.

CAUSE

You cannot modify engine-enforced properties in linked non-Microsoft Access tables because Microsoft Access cannot enforce validation of a field that may be updated by other products, such as Microsoft Visual Basic.

RESOLUTION

You can add a default value or validation rule at the form level instead of modifying the linked table. For linked Microsoft Access tables, you should change engine-enforced properties in the base tables before you link them.

REFERENCES