How about a workbook open macro, asking for a password, and closing the book if incorrect?
Code needs to go in 'ThisWorkbook'
Private Sub Workbook_Open()
Dim myval As Variant
If CDate("02/12/2018") < Now() Then
myval = InputBox("Workbook expired, enter password to use")
If myval <> "Password" Then
The only issue with that is if they disable VBA, that code will never run.
I have seen people try to do some things with hiding all the data, and you have to run VBA code to expose it. That being said, Excel security is not that great and can be bypassed.
What is the purpose of doing this? Sometimes if we understand not only what you are trying to do, but why, we may be able to offer other alternatives.