This is a freshly installed Win11. DOPus will open pdf file with Edge even though in windows setting all are acrobat.
Using Windows File Explorer to open pdf, acrobat will be used correctly.
What and why can this happen? I have been using DOPus for years and this is the 1st time encountered this. Choose "Open with > always" only work for that particular time, not "Always". Please assist.
It happens if the file types in the registry are messed up.
Try reinstalling Adobe Reader over the top of the existing installation, then use Open With again if that isn’t enough on its own.
It also seems to be a feature of fresh Win11 24H2 installations. I have similar problems with .js and .txt files.
I could associate .txt files with Notepad++ by changing the setting while running it elevated. No luck with .js so far - will always be opened by WSH instead of VS Code 
Microsoft may have broken the Open With system again. You had to use a command line tool to change things for a while.
Or changes to some file types (or made via some programs) could be blocked by antivirus or by the OS to avoid breaking things with script types.
If needed, changing the double-click event via Opus can override everything else, since that event is part of Opus and not a Windows thing, and it has higher priority than everything else.
Yes. I installed 24H2 last July as Insider Preview, and Open with kept working fine despite an avalanche of installed software.
Now I run a fresh installation (26100.4061) with very few programs installed, but even Sumatra, as the only PDF program, gets overruled by MS Edge.
I guess that's the way to go 
Didn't Opus 12 have this functionality to change file associations built in? Maybe that's something that could be brought back?
Here's what worked in the past when Open With on Windows 10 stopped being able to change things away from one of Microsoft's built-in apps:
That just called into the same Open With UI, from what I remember.
I performed a clean installation of Windows 11 version 26100.4061 and found that this issue only exists in Directory Opus.
This is not windows problem. File explorer has no problem in double click to open pdf file with Acrobat.
I reported this recently. Glad to see it wasn't me.
I just finished a laborious clean install with the latest version of Windows 11 Pro and everything looks and works fine now. I can also report that in the middle of this reinstall, after installing Google Chrome and making it my default browser, Windows switched it back to Edge.
Before installing Chrome I checked DOpus (which I installed first) and there was no entry for PDF at all. I studiously avoided opening Edge at all beforehand. Then, right after installing Chrome I did an 'open-with' in DO and assigned it to Chrome. Then, eventually, once I installed Foxit, I reassigned it and all went as expected.
I agree that there should be a mechanism in DO to change this setting (if possible).
FWIW, I also recently started fresh with Win11 24H2, but I don’t have that problem. I was able to change the association for .txt and .js from the same "Open with" dialog…
What wasn’t working was open archives with the default program. Even though I had already changed it, Opus kept opening them internally, until I thought to check the "Events" tab in Filetypes for "Archives" files: it turns out the left double-click was set to Go (just that). Removing that fixed it. The funny (or strange) thing is that my configuration in Win10 never had that modified, so I have no idea where the "Go" came from.
It seems that other extensions also have the Go command overriding the default for "Archives", like .zip. But removing it there as well seems to do the trick.
It's a problem caused by missing filetype data in the registry.
File Explorer and Opus react to the missing data differently, but it's still missing at the end of the day.
Suggested fixes are above.
This is happening to me too, and it's very frustrating. I couldn't get anything to work, so I changed the "Left double-click" event to open Acrobat (used the same command that's on the Actions tab for Open with).
In the end, I managed to get them opened by Code... only to discover later that doing so disabled the script engine for cscript.exe, preventing my other .js scripts from running. More tweaking...
My takeaway? Don't touch these settings outside the Open with dialog.
You could change the double-click event for .js in Opus without affecting anything outside Opus.
(No good if you want to double-click scripts on your Windows desktop to edit them, of course.)
Yes, that's what I did. Additionally, I changed some buttons from
FileType ACTION=open
to
FileType ACTION=dblclk
Works ok so far 
I wonder what else 24H2 has in store for us. And I can't wait to get my hands on 25H2 
I've got a very similar problem. When I try to open a .cfg file with double-click from within Directory Opus it always gives me this prompt:
I've checked the App settings in Windows 11 and .cfg files are correctly assigned to Notepad:
When I double click a .cfg file in Windows Explorer window it normally opens it in Notepad without that prompt to select a default app.
Fixed in 13.15.3 beta.
Yes, 13.15.3 lets me undo all my changes. Well, the ones I remember, anyway
I tried your recommendation... When I double click on PDF file, Dopus still opens it with Edge even though I re-installed Foxit PDF reader and selected that application under open with. Explorer will open PDFs using Foxit just fine
Solution that might work for sum people. do not double click item. Instead right click and context menu pops up and then click open.
