Filter Query based upon Checkboxes

[olinms01]

I have a form with checkboxes to filter a query. One of the checkboxes is for filtering the query to find null entries.

Here's the code I put into the Criteria field in my query:

IIf([Forms]![MyForm]![A]=True,"Is Null") Or IIf([Forms]![MyForm]![B]=True,"3A")

I read that IF statements don't like the input of null, but I couldn't figure out how else to connect the checkbox to filter null entries.

Any help is much appreciated! Thanks in advance!

[orange]

What exactly do you think this IIF statement should do? (in plain English)

[olinms01]

What exactly do you think this IIF statement should do? (in plain English)

The expression is checking to see if the checkbox on the form is checked and if true, then filter using the "true statement"

So with the code I have:

Is checkbox "A" checked? True: Filter for results that are null - False: Nothing

OR

Is checkbox "B" checked? True:Filter for results that equal "3A" - False: Nothing