format changes after locking cells

[dlquinte]

Hello,

I'm making an excel file that others need to fill in, therefor I locked all cells except those that need to be filled in (the only box that is checked is the one where users are authorised to select unlocked cells).
But then, after locking the worksheet and the workbook, it is still possible to change the format of a cell (like borders etc.) when they use ctrl x or ctrl c and ctrl v. Even references to those cells change, which gives me a lot of errors in other formulas I use.

How can I be sure that absolutely nothing can be changed, except for data entry in the cells, without using pop-ups etc?

Thanks!