The commands through the Command Prompt will not work under Windows 10 unless your user account has ownership of the Windows\Fonts folder, so forget about deleting the fonts through the Command Prompt.

The "official" way of uninstalling the fonts is as follows: Go to Windows Settings (right click the Start Menu and click Settings), then go to Personalization then Fonts. Search for these fonts one by one, then click on each of them and click Uninstall. The list to search is as follows:

PG Text
PGChords
PGJazz
PGMusic F
PGTextj
PGTextje
BeStPlainXZ
BigBand Chords
RealScore Chords

Once those have been uninstalled, please try to run the Fonts installer at x:\bb\Data\Installers\bbfonts.exe, where X is your drive letter.

As the others have said, please be as methodical as you can. For each of the listed fonts, please let us know if the file comes up in the search or not, whether it gives you any problems Uninstalling it, or whether you encounter any other problems during the process, and write down detailed messages as to what happens and any error messages you encounter.

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