Cubase starts in old version (Cubase 10/12 Pro)

Intermittently, when a project is started by double clicking a project file Cubase starts up in Cubase 10 rather than the latest version, Cubase, 12. I have confirmed that Cubase 12 is the default and that my license for It is valid… Possibly related: sometimes Cubase 12, when invoked without referencing a project, fails license check and aborts. The system is windows 10.


This is on Windows side. Please set Windows so it will start Cubase 12 application when using the CPR extension.

Cubase 12 is set as the default application in Windows for .cpr files but Cubase still starts in 10. sometimes with no error message or explanation . Also Cubase 12 sometimes fails the license check although the license shows as valid in license control. Can you explain how either of these would be a Windows issue?

I had an issue like this in an earlier version of Cubase (maybe one of the iterations of Cubase 11?), and it didn’t make sense, because everything on the Windows front was correct, as you have indicated here. After doing some searching, I found a thread on these forums that mentioned they’d resolved a similar issue by uninstalling some of the older versions of Cubase that were still on their systems. I tried a similar thing – I think uninstalling 9.5, which I hadn’t used for ages anyway by that time. After that, the issue with starting the wrong version when double clicking on a project in File Manager went away and never returned, even with future Cubase updates like 12.

The thing is, my issue there was not intermittent. When that was happening, it happened every time when double clicking a CPR file in File Manager. The only way to get the then-current version of Cubase running was to start it up directly, then load the project. (Much more inefficient because of how long Cubase and projects take to load on my system, especially the first time after booting up, so I typically just start the project then go do some other errands.)

The only thing I could think of on why this behavior might happen was if Windows 10 (at least at that point) had some issue with having a bunch of different versions of the same application on the system that could potentially use that file extension association. (If it was 11 I had this issue with, I probably had 9.5, 10, and 10.5 on the system, since the first time I uninstalled an older version of Cubase was when dealing with this issue.)

Good idea. I’ll uninstall the older versions. Might even fix my problem with intermittent lock up.