Been running Cubase 14 with no issues on Windows 10. Upgraded to Cubase 15, still with Windows 10, no issues. Upgraded from Windows 10 to 11 and suddenly Cubase 15 won’t open, all I get is a spinning blue disc. Cubase 14 still opens fine.
Tried all the obvious things, running as admin, opening in safe mode, reinstalling Cubase 15 (including clean install), all to no avail.
Anyone got any ideas? I’ve had a support ticket in with Steinberg since last Friday…
Check if you have corrupted files in your windows:
Run the following line in your command prompt as admin
sfc /scannow
After that you might also run:
Dism /Online /Cleanup-Image /ScanHealth
If you get anything different a message like everything is fine run this:
DISM /Online /Cleanup-Image /RestoreHealth
Have you tried a simple re-install of Cubase?
Hello and welcome to the forum,
couple of questions:
What happens after the spinning blue disc? Does that vanish? Do you have tokill Cubase via TaskManager?
This happens when just starting Cubase, or when opening a project in C15?
Do you get the Cubase 15 splash screen? If so, where does it hang?
Do you get crashdumps? (in “Documents\Steinberg\Crashdumps”), If so, please upload them here (or some fileservice like Dropbox and post a link).
Try this: go to “%APPDATA%\Steinberg” (paste this into the explorer address bar), move all folders named like “Cubase XY_64” folder e.g. to your desktop (you can move them back afterwards), start Cubase 15, which will now have to generate its initial settings from scratch, instead of importing from older versions).
Yep, and a clean reinstall
Hi,
Tried all of these, and although it did flag up and fixed some errors, I still have the same problem.
Did you run “DISM /Online /Cleanup-Image /RestoreHealth” ?
Hi,
Blue disc just disappears, nothing hangs nothing loads. It only happens when opening Cubase 15. No splash screen, and I tried the other fixes you mention.
I have attached the crashdump - I hope this makes more sense to you thamn it does to me!
Cheers
Cubase 15.0.5 64bit 2025.11.11 20.10.35.094-freezedump.dmp (1.4 MB)
Hi,
When I did I got “Error 87 - the Online /Cleanup-Image /RestoreHealth is unknown”
You got that error as wrong syntax.
Do it properly as it is:
DISM /Online /Cleanup-Image /RestoreHealth
Watch spaces before / forward slashes
Also be sure to run it with admin privileges
The dump shows a failure in Cubase during a file read operation, which doesn’t tell us very much.
Did you do the Windows 11 upgrade in place, or was it a fresh install?
I notice a DropboxExt64.87.0.dll and FileSyncShell64.dll are installed, in the crash log
I wonder if disabling those would be worth doing for troubleshooting?
Hi,
It was an upgrade in place.
It looks like win 10 not 11 in the dump file.
Not sure but this could be a system update gone wrong and anyway it looks like a matter of corrupted system files.
oops… that file is from November @BillyBdeMills do you have the one from today?
lol he uploaded the wrong one. 
Anyone could have noticed, except not us! 
Cubase 15.0.5 64bit 2025.11.11 20.10.35.094-fre
Two things of note:
The dump is from November.
It was taken on Windows 10, so seemingly you had some freezes on 10 as well with Cubase 15.
Is this from the right machine?
Which release of Windows 11 did you move to in the end?
When Cubase is frozen, you can force a dump by opening task manager, right-clicking the Cubase process, and selecting the option to create a memory dump.
Pete
Microsoft
Without a proper dump file, the first thing I’d do is try safe mode as it seems VST loading is a common cause for other folks here. Often, that can mean something like iLok needing to be reinstalled after the OS upgrade because copy protection like that rarely makes it through an OS version upgrade.
Pete
Microsoft
Well, that’ll teach me not to try reading dumps while I’m doing an iPhone migration at the same time…