Checking the error is the very first thing you need to do to fix this issue. Filters do not work properly when you have one or multiple errors in your spreadsheet. To ...

Have you ever attempted to resize header columns in Excel by dragging to fit the text? I have, only to find that just when I think I’ve adjusted them correctly, a quick glance down the row shows ...

You’ve used SUM for years. It adds numbers, does its job, and you probably don’t think twice about it. But while you’ve been clicking through filters and building messy helper columns, Excel has been ...