I would suggest that you have the password stored in a table, one of which users will not see.
In VBA, you can setup 3 variables, 2 of which would be global in in a standard module, if not actually placed in a DB file as that would be a better place for it.
Dim PWFail as Long, DateFail as Date
On the click Event of the button, put in the following type of line:
Private Sub cmdCommandButton1_Click()
Dim Response as String, X as Long
If Now - DateFail > .333 Then
PWFail = 0
End If
If PWFail > 3 Then
Msgbox "This table is currently locked out.
Exit Sub
End If
PWRequest:
Response = InputBox("Enter password to continue."

'at this point, conpare the Response variable to the password in the DB. If it does not match, give the user an option to either go back to the switchboard of try again by something like the following:
PWFail = PWFail + 1
If PWFail < 3 Then
X = MsgBox("Would you like to try again?",276)-7
Else
Msgbox "You have been locked out of the option",48
X = 0
End If
If X Then
Goto PWRequest
End If
End Sub
Please note, the above code is not a complete code, but rather meant to show as an example.
Ronald R. Dodge, Jr.
Production Statistician
Master MOUS 2000
When the going gets tough, the tough gets going.