Highlight or lock cells based on a date condition

[ymt19]

I'm creating a resource capacity plan and I'm trying to lock or highlight (in grey) cells from columns K-Z depending on columns C and D. So for example project A starts in Sept 22 and ends in  Sept 23, I want cells K3 to be locked/highlighted as it is before the project start date and same for cells Y3 and Z3 as these are dates after the `project end date. Same for the rest of the rows. Is there any way of doing this?

[#2]

@ymt19 

Lock or unlock specific areas/cells of a protected worksheet

By default, protecting a worksheet locks all cells so none of them are editable. To enable some cell editing, while leaving other cells locked, it's possible to unlock all the cells. You can lock only specific cells and ranges before you protect the worksheet and, optionally, enable specific users to edit only in specific ranges of a protected sheet.

More informations will find in the upper link.

NikolinoDE

I know I don't know anything (Socrates

[#3]

@ymt19 

=(K$2<=EOMONTH($C3,-1))+(K$2>$D3)

In order to highlight cells you can try this rule for conditional formatting.

=$K$3:$Z$7

This is the range the format applies to in the example.