[AccessD] A2K:Make Some pages in a Tab Control Enabled and some not

Hello all
Under certain circumstances I want the user to go to a form "frmPreferences"
that has a Tab Control on it called  "tabMain"
 
How can I (from the error trapping of another form)  spark up the form that
has the tabControl on
it (That bit I can do) and then make certain tabs enabled or visible on that
tab control?
 
Many thanks in advance
 
Darren