Dorico Pro 3.5 files not opening on Big Sur


I saw that there was support for Big Sur, but none of my files created on Catalina open now that I’m running Big Sur. Anyone have a fix?


Did you shut down and restart your computer after installing anything?

Welcome to the forum, micahabrams. What exactly is happening when you try to open your projects? Are you getting any kind of error message? Is anything crashing? Can you start a new project successfully?

If you’re experiencing crashes, please do Help > Create Diagnostic Report and attach the zip file that will be created on your desktop so we can take a look and see what might be going on.

It’s not crashing, just giving me and small textbox saying “Error opening file”. That’s all. I’m able to create new files, I just can’t open old ones.

I have tried to restart as well as reinstalling Big Sur a second time to possibly account for any issues that may have happened during install.

Can you please zip up one or two of the projects that you’re unable to open, and either attach them here or email them to me at d dot spreadbury at steinberg dot de? If you email me, please be sure to include a link to this thread so I know what I’m meant to do with them (I get a lot of email so I need the hint!).

Big Sur will not zip the files either. Would it be okay to send the files uncompressed?

Sure, please email them to me at d dot spreadbury at steinberg dot de.

It does sound to me as if the files themselves have become damaged. Have you tried restoring them from your most recent backup, or the backup you made of your drive before you upgraded to Big Sur? You should be able to plug your external drive in (if you used Carbon Copy Cloner or SuperDuper) to copy the files from there and see if they open OK. Or restore them from your cloud backup service.

If you didn’t make a whole-drive clone before you upgraded to Big Sur, or if you don’t currently have an online backup service, protecting your critical documents, please take the time to set this up now. I personally use Carbon Copy Cloner for whole disk backups and Duplicacy connected to B2 online storage for documents, photos and videos (I used to use Backblaze, but no longer).

One more place to look for working versions of your documents is the Backup Projects folder inside the Dorico Projects folder in your user Documents folder. Every time you save, Dorico makes a copy of the project and puts it in there, rotating them out according to the settings you choose in Preferences.

It’s worth saying that I have never heard of a macOS upgrade damaging any user document in this kind of way before, though I daresay there are horror stories out there. But please do send me some project files and I will be able to determine definitively whether or not they are damaged.