John is right, a virgin SE (i.e., no other version of Halion installed) should work outside Cubase - assuming it works in Cubase (meaning you have the sound libraries, as well as Sonic SE, properly installed)

John's picture points out what to look for.

And given Steinberg says their FREE version will have access to a “…plethora of sound content…” i.e., any Steinberg sound set that’s installed there should be no reason the Cubase included HALion Sonic SE wouldn’t work outside Cubase either – so I was mistaken

https://www.steinberg.net/en/landing_pages/halion_sonic_se_3/halion_sonic_se_free.html

I could have checked but I never re-installed Cubase 9.5 when I built new PC a 18 months ago so only thing installed here is HALion and HALion Soinc (sans SE).

Good Luck

Larry

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