Getting the old value ????

Hi there... Please help me with this...

I have a sheet (Sheet1) and in A1 the value 150.

I'm trying to change that value (150), but with a confirmation because that cell will be locked after click "Yes".

The problem is here: (Using "If MSGBOX") ("Are you sure you want to make this change ?")=NO

In this case, the value in A1 must return to 150 (the previous value)...

How can I do that??

Any help will be very appreciated!


Very thanks in advance.