Last week, I looked at quarantine flags on documents, and wondered what their true purpose was. I think I’ve found it: they can stop you from opening documents, even those which are known to be free of malware and have never been near the Internet. Yes, in macOS the purpose of document quarantine is to get in your way and ruin your day.
A little experiment
Find a document, any document, so long as it has a quarantine flag attached to it. This could be because it was downloaded from the Internet, or has merely been opened by a sandboxed app such as Preview. Then make a copy of it: don’t do this with the original, as by the end of this all you’ll want to with that copy is trash it, as it will drive you crazy.
Select that copy and use the Finder’s Get Info command to change the app which opens it to something other than the default for that document type. It doesn’t matter which app it is, so long as it’s not the default. Once that’s selected, and without applying this change to other documents of that type, close the Get Info dialog, and double-click on the document icon to open it using that new app.
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