What is C:\$Extend\$UsnJml:$J


Just now I found out that this file is taking up 35 GB of space on my C:\ drive.

If I type C:\$Extend\ in the file explorer, it tells me that directory does not exist.

Does anybody know what is the purpose of this file?

Also, how do I delete this file?


Question Info

Last updated January 19, 2020 Views 6,269 Applies to:

Hi Cody,

In regards to your concern, this file C:\$Extend\$UsnJml:$J is an old Windows system file. They are part of the NTFS structure. Windows doesn't use this but other applications use it to keep track of file changes.

We suggest that you leave the file there and you don't have to worry because it will not harm any of your files. However, if you really want to delete it, then you'll need to perform a clean install of Windows 10.

Let us know if you need further assistance and we will be glad to help.

Thank you.

12 people were helped by this reply


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