The solution is similar to these instructions: FLUX Wavetable Synth missing in HALion Sonic SE 3
I’ve edited them for Cubase users:
Windows
- Close all programs.
- Open the “Run” command prompt by pressing the Windows logo key + R simultaneously.
- In the command line of the ‘Run’ window, enter one of the following path shortcuts::
user specific installation (standard): %appdata%
installation “for all users”: %programdata%
Simply use %appdata% if you are in doubt.
- A new Windows Explorer Window opens.
- Locate the folder ‘Steinberg’ and open the folder ‘Cubase 12_64’.
If you can’t find the folder or files, please try again using the other path shortcut. - Delete these files (to keep a backup, simply copy them to the Desktop before):
ContentManager.xml
mediabay3.db
scannedFolders3.bin
Next time you start Cubase, the deleted files will be rebuilt.
macOS/Mac OS X
- Close all programs.
- In Finder, open the Go to Folder dialog by pressing cmd + Shift + G or via the Go menu.
- Enter this path shortcut: ~/Library/Preferences
(Copy and paste recommended.) - A new Finder window opens (Preferences).
- Open the contained folder ‘Cubase 12_64’.
- Delete the following files (to keep a backup, simply copy them to the Desktop before):
ContentManager.xml
mediabay3.db
scannedFolders3.bin