I have saved an excel file.
I am talking about Sheet1 only.
There are values and formullas in cells of Sheet1.
File is not password protected nor do I want to protect it.
I want......
1. When any cell is selected by someone , and edited to a new value

It should automatically cancel the changes and bring back the last value in the cell which can be a formulla or a text/number.

And then pop us a message box with ok button, that changes on this cell is not allowed.

Need to use VB only, no tools.

Thanks in advance

use the "after update" event handler and do the code in macro

if (cellA1.value <> actualValue) then
select.cell("A1")
activecell.formulaR1C1=actualValue
msgbox("Changes on this cell is not allowed")
end if

something like this