Message box for any value that changes?

[lloyd frank]

Is it possible to have a message box popup if a populated field is changed on the worksheet. I have a workbook that is used for bingo and several people use it. Some of them are not use to computers. I would like a way to warn them if they are changing a value that has already been input.

I have attached a copy of the sheet that I need help with.

Thank You

Lloyd

[alansidman]

How about password protection so that only those authorized to make changes are able to do so. All others can only review and not make changes. Would that work?

[lloyd frank]

It is protected on all cells that does not need input. It is the cells that needs values in that I am trying to bring to their attention if they try to change the cell after a value has been entered. Hope this explains it so you understand what I am trying to do.

Thank

Lloyf

[lloyd frank]

It is protected on all cells that does not need input. It is the cells that needs values in that I am trying to bring to their attention if they try to change the cell after a value has been entered. Hope this explains it so you understand what I am trying to do.
sorry about the double post.
Thank

Lloyd