I'm sure this should be simple, but I am just missing it. I have a field on a form that calculates the difference between a beginning time and an ending time. The results os this calculation are not being put into the underlying table and I don't know how to make it do it. I need the results so I can base a query (& report) on the table and use the calculated result as a criteria. Thanks for any help!!

You don't need to store the results of a calculation in a table to use them as selection criteria. You can perform the calculation in the Where clause.

The form is not storing the results of the calculation because the results field on the form is not bound to the results field in the table. Instead of putting the calculation in the results field, put it in the AfterUpdate event of the ending time control. Then you can bind the results field. There is one little problem with this. If the user does not progress from field to field as you expect, both values required for the calculation will not necessarily be available at the time the AfterUpdate event of the ending time is fired. You will probably also need code in the beginning time field to take care of this.

I DO want the results posted in the table AND displayed on the form in the field that I now will bind to the field "Minutes Down". Once I put the calculation in the After Update on the "Back In Service Time" field, how do I tell Access where I want the result of the calculation to be placed?

send me a solution , i want to send calculated field on a form to a table

There are some here who if they saw you attempting to commit suicide would try and take the gun away from you, there are of course others who will give you the bullets.
You'll have to wait for the latter to turn up, probably next week, and the best of luck

Stop posting duplicate questions
http://www.access-programmers.co.uk/forums/showthread.php?t=14532