MsgBox if any cell within range is blank

This might confuse things further but I also have conditional formatting grey out some cells that don't require completion depending on what category is selected, I think the current code still colours those cells in yellow as they are left blank and then the conditional formatting just puts the grey over the top (so the yellow isn't visible). I would need the error message to only count blank cells that the conditional formatting doesn't grey out. Is that possible?

The code can't detect whether a cell is colored due to conditional formatting. The only way to detect this in code is to use the same logic in the code that is used in the conditional formatting.

Can you attach your file?