What is __MACOSX?

This is a question that comes up a lot, particularly from Windows users. So what the devil is the folder called __MACOSX and what can or should I do with it?

The technical term for what is contained within this curious folder is a resource fork. What a resource fork is is outside the scope of this short article but the Wikipedia article covers it nicely if you’re interested.

__MACOSX, as you may have gathered, will only be created on an Mac. If you’re creating files on Windows, you won’t ever (unintentionally) create these or see them.

However, a common place windows users do see these is in ZIP files that they download or files that they share with Mac users.

Outside of a Mac, they are useless. Depending on who you ask, you may get told that they’re useless fluff wherever they are – a debate that I’m sure will continue to rage on. The point being they do actually have an intended purpose in the OS X operating system.

So, why do Mac Users keep sending them to me if they’re useless?

The answer to this one is that Mac users simply don’t see these folders. Take the ZIP file that you’re looking at and have a look on a Mac a hey presto, just like magic, they’re invisible. And they aren’t the usual type of hidden folder. They’re really hidden! Hence why Mac users won’t remove them from the archive before they distribute.

Can I Delete The __MACOSX folder?

On Windows, absolutely – it’s no good to you at all. Just useless tat taking space up. On Mac, you can’t see it anyway.

The main complaint is that these files can, on occassion, take up massive amounts of space. Usually, they are KB’s so apart from cluttering up your file system and MFT the space they take up isn’t usually of a concern.