Access VBA - Turn off aggregation when opening form/sub-form - ms-access

Question

What I'm trying to do is, whenever a user opens a form (and the sub-form that opens by default), I want to search through all the columns (controls?) on the form, check to see if they are currently set to aggregate (sum, count etc.) with Access' built-in Totals row, and if so, set them to not aggregate.
The reason for this is there are several millions records that are stored, so when someone queries it down to 3-4 and turns on Sum, then closes it, when the next person opens it, it tries to sum millions of numbers and freezes up. The form displays the queried results from a table which is populated via SQL (I think, if that sentence makes sense). Here's what I have so far:
Private Sub Form_Load()
'this form_load is in the UserApxSub sub-form, for reference
Call De_Aggregate
End Sub
Private Sub De_Aggregate()
Dim frm As Form, con As Control
Set frm = Forms!UserAPX!UserApxSub.Form!
For Each con In frm.Controls
If con.ControlType = acTextBox Then
If con.Properties("AggregateType").Value <> -1 Then
'crashes on following line
con.Properties("AggregateType").Value = -1
End If
End If
Next con
End Sub
I have not so much experience in Access VBA (usually work in Excel VBA) so please forgive me if I'm entirely off the mark here. The command con.Properties("AggregateType").Value = -1 doesn't throw an error, but Access just straight-up crashes when reaching that line specifically.
I've tried a number of variations in the syntax with no success, and I've also tried looping through other elements of the file (tabledefs, querydefs, recordsets, etc.) as well to see if I'm trying to change the wrong value, but the controls on this subform are the only things in the entire .mdb file that results when I search for elements with the AggregateType property.
I switched out the line that errors with Debug.Print con.Name & " - " & con.Properties("AggregateType").Value and I can check, have nothing return anything other than -1, turn on aggregation in some column manually, and have it return the correct result (0 for sum for example), so I think I'm looking in the right place, just missing some key factor.
I've been working on this for a couple weeks with no success. Any way to fix what I have or point me toward the right direction would be greatly appreciated!

Answer 1

This is not necessarily the answer but I don't have enough reputation
to give a "comment"...
I tried your scenario and verified can change the property value as you are however I did not iterate through all controls and simply used an onDoubleClick event on a column to simulate.
I would suggest trying to fire your sub with Form_Open or Form_Current to see if the property is getting reset after your code has been called for some reason.
UPDATE:
You are referencing the "Subform" Object of your main Form:
Set frm = Forms!UserAPX!UserApxSub.Form!
Try referencing the actual UserApxSub FORM explicitly.
Something like Set frm = Forms!UserApxSub! (assuming UserApxSub is the name of the form)
then stick in the Form_Open of your main form:
Private Sub Form_Open(Cancel As Integer)
'// the following would set a single control only. You can add your loop through all controls
Me!{your control name}.Properties("AggregateType").Value = -1 '// set control in your main form
Form_UserApxSub!{your control name}.Properties("AggregateType").Value = -1 '// set control in your "sub" form
End Sub