Lock range of cells until a single cell is edited

Hi All,

Not sure if something similar is already posted, however my VBA experience is non existent.

Please see attached file.

What I am trying to achieve is that when the spread sheet is opened cells C8 to F17 are completely locked so that no data can be entered. When cell C2 is edited and a value entered, then cells C8 to F17 are unlocked and editable.

This is where I am struggling, cell C2 is a predefined list using data validation. Cells C8 to F17, will either be a predefined list, date input only, number input only or free text input only all cells having data validation for these already.

To simplify this example more, in cells C8 to C17 is a predefined list using data validation. Then when I open the spread sheet and Cell C2 is blank, I cant adjust any cells in C8 to C17. When I pick an item from cell C2, then cells C8 to C17 become active and able to select from the list for that cell.

I believe there is no way to do this using just data validation and protection of the sheet only and requires some sort of VBA code.

Thanks.