The control source property of the selected control in Access is not a valid expression or field name.
You can do one or more of the following:
To edit the Control Source property in the property sheet, click Edit the Control's Control Source Property on the Error Checking Options menu.
To edit the Record Source property of the form or report, click Edit the Form's (or Report's) Record Source Property on the Error Checking Options menu.
To ignore this error and hide the Error Checking Options button, click Ignore Error on the Error Checking Options menu.
To turn off error checking for controls with an invalid control source, click Error Checking Options on the Error Checking Options menu. On the Error Checking tab, under Form/Report Design Rules, clear the Invalid control properties check box.
Note: You can also access the Error Checking settings by clicking File > Options. In the left pane of the Access Options dialog box click Object Designers. The Error Checking settings are at the bottom of this tab.