macro to undo user changes since last save

[nguye569]

Hi I would like a macro to undo all user changes since the last time it was saved.
Basically, I have a worksheet that requires users to enable macros before they use it because it can still be used without enabling macros and can give incorrect results if done so.

All sheets are hidden and unhidden when user enables macros and clicks button.

On close, if worksheet is detected to have been saved already. then macro will rehide all sheets except for 1, saves itself, and closes.

If worksheet has not been saved, a form shows up asking if user wants to save.
Click yes, then the macro hides all sheets except for 1, saves itself, and closes.

Click no is where I have a problem.

In the case where the user has inputted data already, clicked save, and inputted more data - I want the no button to undo all changes leading up to the last save, rehide all sheets except for 1, save itself, and close.

Is this possible? Any help would be appreciated, thanks!