Changed Instrument List unexpectedly

In selecting or changing instruments, I found ‘Violin’ in Strings Group had been changed to Solo Vn., and 'Classic Guitar in Fretted Instruments had been removed. As to Violin, instrument name in scores are correctly shown. How to repair these instrument data?

In Setup–Player List–Click on Instrument–Edit Names, there’s a button at the bottom right corner of the Edit Names dialog box to “Reset to Default.” That should restore the instrument names to their factory settings.

Full Name and Short Name returns to default, but the top-left corner box remains to greyed ‘Vn. Solo’.
By the way, desappeared ‘Classic Guitar’ problem was because of switcing lungage to German. So it chenged to K…, Sorry.