Numerous Layers of "Application Data" in Users\All Users may be causing bloat

Win Filesystem:
In C:\Users\All Users there is a folder called "Application Data" for some reason with a space in the filename, as has "All Users" directory (not the best of practices) . There's No "AppData" directory in "All Users"
When I open "Application data" directory there are a bunch of folders for various applications, as expected BUT another "Application Data" directory. What is in the top level Application Data is in the this next level down Application Data directory too and in the one below...
From thereonafter it's turtles all the way down.
I stopped counting at 20 layers of nested Application Data directories but continuing crashed Explorer.

I'm not sure if the directories contain files or if it's shortcuts (to a long scenic route), pointers, symbolic links or what have you. I'm no coder, BTW.
What could be causing this? A third party software application? If so how might I trace that?
Windows misconfiguration?

As getting to the bottom layer crashes Explorer I can't copy from there to the top layer and overwrite after comparing directories and files.
Can I just delete lower layers. I'm reluctant to as even though I think they all contain the same data I can't be sure if some application has written to the bottom layer (which I can't get to, let alone open as it crashes Explorer).

Is it something to do with the directory name having no space? Then Third party developer missed quotations?
The folder when I could check properties (I can't now) was 950 GB - excessive as I keep most of my data on other drives.

I reinstalled Win 11 on Saturday night, updated today and checked integrity with SFC and DISM. Before reinstalling there were 9 levels of nesting, now >20.
Any suggestions please?

Make copies of your data and a clean install of Windows.

Hi, Frank, welcome to the ElevenForums

I’m with abactuon on that one. Backup and start over. How does that even happen?

C:\Users\All Users is not a folder; it's a symbolic link to C:\ProgramData. If you look in ProgramData, you'll see the same contents.


As is the Application Data "folder" inside All Users.

FrankE said:

When I open "Application data" directory there are a bunch of folders for various applications, as expected BUT another "Application Data" directory. What is in the top level Application Data is in the this next level down Application Data directory too and in the one below...

[snip]

What could be causing this? A third party software application? If so how might I trace that?
Windows misconfiguration?

Click to expand...

By default, the Application Data symbolic link has a deny ACE on it for Everyone, to prevent users from opening it and listing its contents. So the fact that you're even browsing it suggests you or some other app modified the permissions on at least this entry, which shouldn't have been done.

FrankE said:

I reinstalled Win 11 on Saturday night, updated today and checked integrity with SFC and DISM. Before reinstalling there were 9 levels of nesting, now >20.

Click to expand...

Did you install any third-party apps afterward? Or did you mess with the file system permissions?

Application Data is a Junction or Hard Link. It points to AppData. Did you play with any permissions on any of your system folders, like a deny permission or changed any part of the security settings?
Regardless, I’d start over. Or you could try some old software called ”Junction Box” but I have never used it.
It’s available on sourceforge .net.

@FrankE

You shouldn't be able to open C:\Users\All Users\Application Data





If you took ownership of that folder, you may have broken something.

Some folders you can get away with taking ownership, some you can't.
Most of us that experiment with Windows, use backup software.
That way, when we break something, it's easy to fix.... just restore from a previous backup.



Here are some things that might help on your Windows 11 journey....

abactuon said:

Make copies of your data and a clean install of Windows.

Click to expand...

I'm thinking that, or (somewhat optimistically) was thinking to reinstall all application software to overwrite permissions or live with it until new build time, install on a freshly-formatted disc, install applications and copy settings, configs and data over the network to new machine.
ACLs must be all over the shop.
There's the same nest of Application Data\Application Data\Application Data in C:\ProgramData I had to go in there to find and restore a database and settings. That was months ago.
I backed up the Users and ProgramData directories on Saturday night with Robocopy before installing Windows 11. I had to reinstall MP3Tag and restore settings from myusername%APPDATA%\Mp3tag
There aren't many software apllications on my pc, there's only my a/c and Administrator, no guest a/c as I don't want potential guests interfering with my settings..So I'm looking at software that installs for all users. Software that is listed in all users\Application Data and not in corresponding directories under my own username to find the offending software?
Maybe that piece of software that works for a bit, stops working and I have to reinstall using Python commands from instruction sheet because it was a Linux programme. I have my suspicions. My next port of call was to ask on their forum if anyone has had the same issue.

The permissions on C:\Users\All Users won't be fixed by application reinstallation - this is set by Windows during install, and as such, will more than likely need a re-install.

pseymour said:

By default, the Application Data symbolic link has a deny ACE on it for Everyone, to prevent users from opening it and listing its contents. So the fact that you're even browsing it suggests you or some other app modified the permissions on at least this entry, which shouldn't have been done.

Click to expand...

One thing you could try is an in-place 'upgrade' to try to reset Windows without losing your currently installed apps and data.


At this point it's well worth a shot, since it would take a lot less time than a full clean install, including backing up app settings from numerous locations, reinstalling Windows, then reinstalling your apps and finally restoring your settings. Now, I do this often enough that I have a good routine down, plus I have multiple internal drives and split \Users from the system drive to a separate physical drive, so it's a lot easier for me. But even I've found that sometimes, an in-place upgrade to repair Windows is just a better way to go.

If you do decide to go this route, be sure to use a Windows Installation ISO that is at least the same build as you're running now, (newer is OK). If you need to get a specific version ISO, check out the UUPDUMP tutorial which takes you step by step on how to make one:


Also, unless you set Explorer to show all hidden files, including protected os files, you should not see \All Users in the first place.

I have mine set to show hidden files but Hide protected os files, as such:



If you explicitly uncheck that box, then you can see both \All Users and even \Default User, and that is even before you start looking at permissions to access those normally inaccessible folders like \Application Data.




If the in-place upgrade works, you might then be able to track down which application did this, assuming it was one of them....