The phrase "red exclamation" refers to a symbol, usually a red triangle with an exclamation mark inside, which represents a warning or urgent message. Full definition
But alas, this is not the case, as in order to find story missions you are required to scan the area while keeping vigilant watch for red exclamation points. (shortpause.com)
So the next time you get a pushy email in your inbox with a little red exclamation mark meaning «urgent,» and looking for the latest version of that spreadsheet now now now, you can probably pause to take a breath. (canadianbusiness.com)
Check if any recent events show a round red exclamation mark error icon. (thewindowsclub.com)