Image file associations on Windows 11 (LTSC, 24H2)

[User097]

Hi all!

I searched through all the threads related to this issue and found nothing of value. But the problem definitely requires attention and a solution.

Regardless of how I configure graphic file associations with XnView, after a reboot, everything reverts to the built-in Paint app. I tried using the built-in Windows "Default Apps" app, the registry, SetUserFTA, and even wrote a script in LLM that I planned to install at startup to re-associate files each time — nothing helped.

1. Is this problem only happening to me on Windows 11?

2. If the problem was observed by everyone, how did everyone solve it?

Thank you for your help.

[user0]

maybe you have not registered portable app in the system

these 2 official ways of association in Windows 11 should always work:
- Settings > Default apps
- Context menu > Open with [Always]


ps SetUserFTA 1.8.3/4 still works fine for me on win11 25H2 enterprise

[User097]

Thank you for your response.

I've already noted that associations assigned through the system app are lost immediately after a system reboot. In XnView itself, the "Associations" section in the settings is disabled.

I have XnView installed, not the portable version.

SetUserFTA doesn't work at all. I suspect I'm doing something wrong, so I'm attaching the registry file and the program itself with a .txt file.

And one more thing. After rebooting, the following window pops up:
https://ibb.co/1GDF4XRG
which in translation means:
"Default app reset The app caused a problem with setting the default app for .gif files, so it was reset to Paint."

It's probably worth investigating. The problem seems to be specifically with GIF files.
Your thoughts?

[user0]

add some missing keys into registry before association, see updated
XnViewMP - integration - file association

[User097]

It doesn't work.

I even have an idea to replace it
C:\Windows\System32\mspaint.exe
C:\Windows\SysWOW64\mspaint.exe

xnview.exe file, specifying the XnView installation folder in the system variables. It's unlikely to work, as the system will likely revert to the original MSPaint, but it's worth a try.

[user0]

It doesn't work.

try with admin rights

[User097]

In Windows 11 24H2 or Insider Preview, Microsoft has «strengthened security», and SetUserFTA no longer works for most file types. This has been confirmed by the utility's author.

I developed an original utility AppAssociator for intercepting Paint calls (mspaint.exe / ProgID PBrush) on XnView, which is located in the D:\Software\XnView\ directory.

You can download the application source code and compiled binary from the repository: github.com/Balans097/AppAssociator

In theory, the .exe file should be set to startup, and it will re-associate the files after each reboot. But for some reason, it works for me even without startup. Perhaps I changed something in the system during my experiments, and I don't need to run AppAssociator every time.

Enjoy! I'll be expanding the app's functionality to other problematic file extensions in the future.

[user0]

issue is caused by app incorrectly registering itself in the system
it should be fixed in the next version

[User097]

Okay. Good.

In any case, I've already developed a fast and efficient solution for myself in the Nim programming language. It runs in milliseconds, since it's C. I've made it publicly available. Perhaps someone will find it useful.

[User097]

Although the problem being solved affects a wider range of users than XnView users, I will report it here.

Updated the utility, adding NotePad++ support for txt and log files. This also crashed for me. I also updated the guide on how to customize the app to support an unlimited number of other associations.

github.com/Balans097/AppAssociator