When a cell is formatted to hide its formula in a protected sheet, it’s ambiguous to the user what will happen in the spreadsheet when he changes values, formulas or the structure. It’s better to unhide the formula, by right-clicking the cell range and choose ‘Format Cells’. Then clear the ‘Hidden’ checkbox under the ‘Protection’ tab.
Hidden rows / columns
As with hidden formulas, hidden rows and columns potentially obscure the way a spreadsheet works. Contrary to hidden formulas, columns and rows can be hidden even when the sheet is not protected. You can always unhide rows and columns by right-clicking on the column/row and selecting ‘unhide’.
While hidden info obscures potentially important information, it is especially risky to add formula or cell references to this hidden information. Hidden information is easily overwritten or forgotten!
Worksheets that are hidden potentially conceal important information to understand the working of the spreadsheet. To unhide a worksheet, right-click any worksheet and choose ‘Unhide Sheet’. A popup will open, where you can select the sheets you wish to unhide.
Very Hidden Worksheets
A sheet that is ‘Very Hidden’ gives the impression that it is secure, because users don’t see it when they look for hidden sheets. It can however be modified without any additional authentication! A ‘Very Hidden’ worksheet is considered a high risk by default. PerfectXL reveals any ‘Very Hidden’ worksheets immediately. To unhide ‘Very Hidden’ sheets, you need to open VBA with Alt F11, then go to ‘Properties’, go to ‘Visible’ and choose option “-1 xlSheetVisible”.