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I have a folder of MP3 songs. In Windows Explorer and when doing "dir" in cmd, I see:

01 One More Time.mp3
14 Too Long.mp3

However, there exists a file folder.jpg and I can access it by simply typing it into the Explorer address bar, and Winamp and Windows Media Player can all see that file. In Cygwin, when I do ls, I get:

01 One More Time.mp3
14 Too Long.mp3

This is really weird. I can overwrite the file folder.jpg with an editor like Vim, but if I download something from Firefox to replace it, Firefox says it cannot modify it since it already exists. Presumably, Firefox uses a Windows API to create the file since a "dir" does not list it, but somehow Vim dir-ing it finds it.

I am on Windows 7 Ultimate. Show hidden files is turned on.


So I just turned on Show System Files, and these appear in Explorer, the icons kind of greyed out. Why on earth are these system files? I manually created the folder.jpg file. Firefox still cannot overwrite that file with a download.

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Is "Show system files" turned on? – Hello71 Aug 23 '10 at 18:39
No it's not. Now that it is, it shows up. But why are these system files? – oliverzheng Aug 23 '10 at 19:03
What music software do you have installed and watching this folder? I know that the Zune software can add a bunch of extra files to manage the album art. It could be that a program is setting this file to system. – Doltknuckle Aug 23 '10 at 19:16

Apparently Windows uses a convention whereby a file named "folder.jpg" located in a given folder is used as the thumnbail image for that folder; so the problem is specific to that particular file name.

Some info on this: Here and here and here

I guess they're considered system files because if you make a folder full of images, this file is automatically created by Windows and is used in Explorer, My Computer, Windows Media Player, possibly other places, etc.

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You can open a command prompt and navigate to your directory with the hidden files. Then type

attrib -H -S folder.jpg

Replacing folder.jpg with the other file names also

share|improve this answer
attrib -H -S folder.jpg /s This will (of course) fix this file in all your subfolders too. – stevemidgley Jul 21 '14 at 20:02

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