Open your form in design view.
Select the “Last Update Date” control.
Activate the Properties window, Events tab
Click in the AfterUpdate event.
If it hasn’t been selected, select Event Procedure.
Click the builder button (the three dots …)
You should be taken to your procedure.
Switch back to Access, and save the form.
Test if AfterUpdate now works.

Try the following:

Repeat the steps from my previous reply until you are in the Visual Basic Editor (or return there if it is still open).
Click in the margin to the left of the line Private Sub Last_Update_Date_AfterUpdate()
The line should be highlighted in brown, and should be marked by a brown bullet in the left margin. This is called a breakpoint.
Switch back to Access, and open the form. Change the date and press Tab or Enter.
You should be taken to the Visual Basic Editor, with execution of the event procedure paused at the breakpoint.
If that doesn’t happen, something must have gone wrong when you followed the steps from my previous post.
If it does, single step through the code by pressing F8 repeatedly.
Does the highlighted yellow line move down, and disappear when you’ve come to the end of the procedure?

I’m afraid I don’t understand why it doesn’t work. Let’s try something different.

In Microsoft Knowledge Base Article 210236, Microsoft describes a method of filling one or more fields in a new record with values from the previous record. You can also download a sample database with a form that demonstrates this method. I hope that you can apply it to your database.

I hesitate to ask it, but if you wish, you can attach a stripped down, sanitized, compacted and zipped version of your database to a post. That way, other Loungers can try to pin down the problem. Remove everything that is not needed to demonstrate the problem. The zip file should be less than 100 KB.

It works! But what in heavens name is your purpose? The form doesn’t allow adding a new record, so you’ll never see the effect of setting the default value!

I have set Allow Additions to Yes, and added code to set the default value (and optionally the value in the current record) of Held Net Outstandings to the value of Managed Net Outstandings.

Defaults only apply to new records. Do you mean you want the rest of the records *updated* to the new date? *All* existing records?

Something like this will change the date when it is changed in any record, not just the first one:

Private Sub Last_Update_Date_AfterUpdate()
CurrentDb.Execute “UPDATE Vendors SET [Data Date] = #” & Format(Last_Update_Date, “mm/dd/yyyy”) & “# ”
End Sub

But, as you will find, this causes a conflict. You should only set the date for other records. For this, you need a unique key, for instance an AutoNumber field VendorID. Then you can use

CurrentDb.Execute “UPDATE Vendors SET [Data Date] = #” & Format(Last_Update_Date, “mm/dd/yyyy”) & “# ” & _
” WHERE VendorID ” & VendorID

In the Visual Basic Editor, select Tools/References…
Uncheck any reference starting with MISSING, and also uncheck the Microsoft DAO Compatibility Library (or something like that), then click OK. Switch to Access and try the form.

Check very carefully if the table name and field names are spelled exactly as they are in the table. The field name for vendor number may very well be Vendor Number, in which case you must use

” WHERE [Vendor Number] ” & Vendor_Number

Well, that’s one less than before, so you’re halfway there

On looking back at your database, I notice that Vendor Number is not a number, but text. (Long live consistency). Should have remembered that. That means that the value must be enclosed in quotes. Try

CurrentDb.Execute “UPDATE Vendors SET [Data Date] = #” & Format(Last_Update_Date, “mm/dd/yyyy”) & “# ” & _
” WHERE [Vendor Number] ” & Chr(34) & Vendor_Number & Chr(34)

ASCII/ANSI character 34 is the double quote “.