Filter by color option not available
With the data autofilter you may discover that filter by color option is not available. There are a couple of possible reasons for this.
The first reason is if there is only one colour in the selection. So if all the cells are for example yellow, then there is nothing to filter on and the ‘Filter by color’ option will be greyed out. Change one of the cell’s colours and you should be able to use the filter by colour
A more obscure reason is that the spreadsheet is in sharing mode. When this is true then for some reason the filter by color is not useable. To check if you workbook is shared you can go to the REVIEW tab and click on the SHARE WORKBOOK button. If the ‘Allow changes by more than one user at the same time. This also allows workbook merging’ option is ticked then it is a shared workbook. Untick it to switch it off and the filter by colour should reappear.