What do these two blue arrows mean?

QI’ve been using Windows 10 happily but recently stumbled on something curious. Specifically, I noticed that one of the folders I use to store pictures has two blue arrows at the top-right of the folder icon, pointing inwards and towards each other. I have no idea what these arrows mean, or why they appear on only one folder. I’ve used File Explorer to search all over my hard drive and I can’t see any other folder with these arrows. I’ve even tried emptying the folder in case the arrows mean it’s getting full, but they remain. Can you clear up this mystery? Is it something I should worry about? How do I get rid of them? John Carlton

AWe sure can. These blue arrows (see main screenshot) indicate that the folder has been compressed using Windows 10’s built-in compression system. We can’t tell you why only this one folder has been subject to this process, but it’s a feature that we’ve mentioned a few times, so it’s possible that you experimented with it and then forgot about it.

It’s absolutely nothing to worry about, and compressed folders free up space on your PC. How much depends on how many files are inside, and how well Windows was able to compress them, but a single compressed folder isn’t likely to save a lot of space. The one side effect is that Windows might run very fractionally slower when accessing files in this folder, but on a modern PC the difference is likely to imperceptible.

To remove the compression (and thus the blue arrows), first right-click the folder, choose Properties, select the General tab and click Advanced. Now untick ‘Compress contents to save disk space’ and click OK twice to confirm (see screenshot above).