I also commented out the AfterUpdate event, but the new blank record still shows up after exiting the ComboBox..

What do you mean by exiting the Combo Box? Do you select a value?

Really not understanding what you are meaning, can you post some screenshots?

It is a combo box that looks up various types of fees (trip, meal, fuel, etc.), then writes the ID into the Fee table along with the quantity and cost.

After selecting the value from the ComboBox and pressing the enter key, a new record appears in the continuous form before the other fields in the current record are filled in.

William -
Go into any of the sample databases or any of the videos that have a continuous form and you will see that the moment you start to add into a new record, Access automatically adds another new record line. It assumes that you will want to add more records.  Whether you are adding invoice line items or contacts or whatever.  (Try it in any of the sample DBs that Richard has produced.)

The only way that I know of to "shut off" that particular feature is in the properties set Allow Additions to no.  Just from what you are describing that is not what you are wanting to do.

There are ways that you could turn that off. Put in a "New Item" button where it would turn it on, add the next line, turn it off, and go to the line to edit it.  Lots of programming but why?
You are better off making sure all of the fields are completed before going to the next item. The courses show how as well as some of the TechHelp videos.  It just depends on what you are doing specifically.

I know I said it before, and at the risk of sounding like a broken record (do people today even know what that is?), Do yourself a favor and follow the courses 1, 2, 3 at least through Expert 2.  You really do put yourself at a disadvantage by trying to just jump into the middle.

Check out the Learning Connection program on the Memberships Page that Richard has set up.  One of the most cost effective ways to get the courses. You get up to 50% off when you are an LC Member!
The best value is the MYLOP.  Check that out also. Click each individual link for more details.

Disclaimer:  I'm not Paid to tell you this.  I don't make anything off of you joining or not.  I just REALLY believe in what Richard has produced.

I agree with Scott. I have no idea why you would want to do this, but, this is how I would accomplish what you want.
Swap out my field name placeholders with your actual field names.

Private Sub ValidateData()

    If (IsNull(Combo) Or Combo = 0) Or _
        (IsNull(Field1) Or Field1 = "") Or _
        (IsNull(Field2) Or Field2 = "") Then
        Me.AllowAdditions = False
    Else
        Me.AllowAdditions = True
    End If
        
End Sub

Then call ValidateData in the AfterUpdate event for each of your fields.

My deep concern is that individuals (Senior Citizens) using the form will drop down to the next record without completing the previous record.  As far as purchasing courses; I'm a "forced" retired IT professional because of the rampant Age Discrimination in the IT field.  No employer wants to hire you when they know you are just a few years from retirement.  I haven't worked since September 2020 and can no longer draw unemployment, so my wife has been supporting us for two years now!  

I'm currently trying to get the money for the Access Security seminar @ $ 269.99 that was recorded with Access 2007; however Richard states on the webpage that it works with Access 2019 and Office 365.  And that only ~20 percent of that class would be beneficial to me.  I don't want to find out it doesn't how to set the Function CurrentUser() to the Login UserName.  

I started out programming in dBase III, Cobol, Fortran, and C+,  so I'm not just "jumping into the middle" of developing a database.

William -
Two thumbs up!  I started with databases in Alpha 4 for DOS.  dB III. LOL  I totally get the budget thing and the age thing, I'm right there with you.
This also gives us an idea of how complicated to make answers (or not).

Security - Go watch the Simple Security.  That will get you pretty far down the line.
I don't know how much SQL you know but honestly I found the SQL Seminar 1 & 2 more valuable for general Access stuff.

Since you are a Gold TechHelp member you can download all of the databases plus have access to the Code Vault.
Get into those and really pull them apart after watching the videos.  You will learn tons by seeing how Richard does things.  Some things that are easy to miss in the videos.  I think there are over 250 TH videos now.  Soooo much there!