Mo_ke

Also having this issue on 10.5.7 build 2171, makes the desktop app unusable as I can't open key notebooks, just whichever one was open at the time of the upgrade.

Experiencing the same issue since upgrading to 10.5.7 on Windows 10 - some notebooks work fine, others giving me the above error message (though the same notebooks work fine in web app). Uninstalling and reinstalling doesn't seem to fix the issue.