Trying to open with 2025 version, opens with 2024 instead

[tuomas.einamoV2MEV]

I am trying to open a backup file of a scene I made with 3ds Max 2025. I still have 2024 installed for various reasons. The file is opened with the 2024 version, which doesn't work since the file was created with a newer version of 3ds Max. 

So I tried to use the choose another app option but no, even if I browse to the executable of 3ds Max 2025, the file is still opened in 2024, failing again. I went looking at the default apps in Windows (10) system settings and noticed that .max had the 2024 version selected. And there was no option to choose the 2025 version. 

How do I fix this? 

[RobH2]

I have this annoying issue too and it's a Windows problem. What I have learned to do is to just always open Max first, then drag in or navigate to the file I want. I know it's not as easy as just double clicking on a file and letting Max open, but it's a way to get around the sometimes silliness of Windows. 

I have tried without success to set the version of Max I want as the default. Because the machine may have three versions of Max on it and all of them are called "3dsmax.exe", Windows can't tell them apart. There is probabaly some involved programmer way of fixing this but I have not found it yet. 

[aschulte2MFAQ]

THANK YOU! I was tearing my hair out trying to figure this out but the drag n drop method worked. 

[CAMedeck]

Yeah, +1 to Rob's suggestion.  I've heard people advise against double clicking .MAX files for many years.  Usually, MS Windows will use the most recently installed version of a software title, but not always.

[spacefrog_]

I think i have a solution to fix this via batch file or powershell script ( requires one run )...
stay tuned ...

[spacefrog_]

I have a dos shell/ batch script ready to test if anybody is interested

Coolest feature is that you can drag&drop you preferred 3dsMax.exe onto the script ( or onto any shortcut to the script ) and after confirmation prompt, associates .max files to the newly dropped 3dsMax.exe
BTW: doesn't touch anything else ( icons etc.. ),  just changes the 3ds Max version that gets launched...

Works flawlessly for me , but i would need some people to test it before general release ...

Anyone ?

[RobH2]

I'll test it. 

[spacefrog_]

Thanks rob , check your PM please 🙂

[spacefrog_ · Accepted solution]

I guess i found a more direct route to fix this using just  one command in the commandline

• run an elevated command prompt ( RMB-> Run as Administrator )
• copy&paste the line below and edit it to point to your preferred 3ds Max installation
  ftype 3dsmax="C:\program files\Autodesk\3ds Max 2025\3dsmax.exe" "%1"
• hit enter and if required, confirm the "User Account Control" prompt

That should do the trick, please report if it does...
maybe i still release some script that makes that even easier... lets see

[RobH2]

That worked. Nice going Josef....  Thanks for the hard work. I spent a few hours on it this summer and gave up. 

Thanks again, this will help a lot of people. 

[spacefrog_]

Thanks Rob2. And thank you testing !

[alex.chernyh]

You could use Windows Regedit program to make changes in Windows registry file.

In Regedit:

• browse to HKEY_CLASSES_ROOT\\3dsmax\\Shell\\Open\\Command,
• double click on the (Default) entry
• and edit the path so it points to the 3dsmax.exe you'd like to use by default

(make sure the path is in quotes as there are spaces in the path and leave "%1" at the end so 3ds Max will open the file you double clicked on).

Computer\HKEY_CLASSES_ROOT\3dsmax\Shell\Open

[spacefrog_]

@alex.chernyh: This is the legacy, pre Win10 way of file associations.
My first adempt using a HKEY_CLASSES_ROOT\Applications assignment was another legacy way, which in turn did'nt work on RobH2's system. Honestly - i would recommend against doing this directly via registry association,as it makes the whole registry setup even more confused and probably only work on certain systems. It also may break future *.max file associations done by a future 3ds max installer.

The W10 and up way to do it is using "assoc" and "ftype" shell commands

[alex.chernyh]

I still use this method in Windows 10 Pro and it works fine.