Error: "Argument is not an option" on Macro

[Luminary Xion]

This Thread describes a function that I've found incredibly useful to reset the "last used cell" in a worksheet.

I use this function a lot, and I would like to make a macro out of it. I have a menu-item added in my excel that runs the macro;

Public Sub Reset_lastcell(wS As Worksheet)
    ActiveSheet.UsedRange
    wS.UsedRange
End Sub

But attempting to run it gives me the error "Argument is not an option".

Just copying and paste the code into the "view code" for a worksheet will reset the "last used cell" when a spreadsheet is openned. See above mentioned thread for more detailed descriptions of the problem this solves.

Please advise on how I can a. fix the menu-item I've created to make it solve the problem described in the above linked thread, or b. help me come up with another option to use (repeatedly, so hopefully easily) on multiple workbooks with this problem.

Thanks!
My Last Try At This