If you are getting an error 3155, you could check for it in your error handling code.
However, this would be an after the fact confirmation that someone was attempting to modify/insert/delete a record in the linked table.
In your code to limit user rights, if the user is a ReadOnly user, you could display a msgbox or a modal form that they had to see and react to in order to continue. And you could have an error handling routine to tell them again.
Below is untested code ---air code to show the general logic involved ----
Code:
If userType is ReadOnly Then
MsgBox "You have READ ONLY access to tables. Any attempt to edit, insert or delete a record will fail",vbInfoOnly
end if
IN the error handler
Code:
If err.number = 3155 then
MsgBox "You do NOT have authority to modify, insert or delete records", vbOKOnly
else
msgbox err.number & " " Err.description, vbOKCancel
end if