Access 2010: Link subform history to current record when ID numbers are different

In design view, select the subform container. Make sure you select the container and not in the subform itself. In the properties window you should see these 2 properties: Link Master Fields and Link Child Fields. See my attached image. In your db, do these have data?
MS-Access-2010-subform-link-fiel.png

Hi Lee - Yes - there is a lot of data. 18,000 records in tblInqiryFile (what the current form should be returning and is on the main tab of the form and 65000 call history records (from tblcalls) for those in the subform.  All calls are currently showing in the subform.

Responding again --- You definitely pointed me in the right direction!  --- I  successfully linked the call table to the current record on the form using the master and child fields.   BUT --- since those linked ID's are "old ones" - and not new ones, I can't add a new call record to the file.  I'm getting the following error: "Index or primary key cannot contain a null value" --- this is happening, i think, because to show this history i'm linking the current record of the primary input form to the subform via "oldInquiryID" from the underlying primary table with the "OldInquiryID" from the subform underlying table "tblcallhistory" .... those numbers are just numbers.  the New ID, [ID] in tblInquiryFIle is the primary key of that table and [callID] is the primary key of the subform table, tblcallhistory.  

Now what? :-)

You've been helpful to this point immensely --- hopefully we can resolve this!
Michael.

It's ok --- you pointed me to the right place last night.  It's all working now!!   --- well mostly :-) ---    Now i'm I'm on a new path to find out if I can use a button on my Access Form to Open Outlook Calendar when an appointment is made..........  

thanks for your help!!
Michael