How do you make a control source

I built a database years ago in Access 2000. I have Access Vista now and am
wanting to add a field for update info, such as the date the data was
updated. When I enter a date it changes it on every form, each form will
have it's own updated date.
I have a field with birthdate and was able to put in the birthdate I am sure
this works because I have a control source named "birthdate". I think I need
to create a control source "update" to get this to work but for the life of
me cannot remember how to do this.

Hi Jul,

Add the field to your form's underlying table first. Then you can use
it as a control source for your field on your form and it will reflect each
record's value as you go from record to record.

Clifford Bass

"Jul" wrote:

I built a database years ago in Access 2000. I have Access Vista now and am
wanting to add a field for update info, such as the date the data was
updated. When I enter a date it changes it on every form, each form will
have it's own updated date.
I have a field with birthdate and was able to put in the birthdate I am sure
this works because I have a control source named "birthdate". I think I need
to create a control source "update" to get this to work but for the life of
me cannot remember how to do this.