When I try to load into Kontakt standalone any .nki or .nkm (instument or multi patch) from EWQLSO Silver Edition (that comes with Kompakt player) or GPO (comes with Kontakt player, just as Sibelius Kontakt Silver or Gold) it gives me this error:
"The content you are trying to load is not registered! (please be sure to start the applications that came with the content at least once)"
I say ok and then says "The patch could not be loaded (unknown error)".
I have to say that I have those libraries already registered, and ran at least once
There's a content key in the registry that didn't get updated. This is a known bug which has been reported to Native Instruments.
There have been posts on this in the past so you may want to try the search function. Also, hopefully Gary Garritan still has the fix I sent to him. Unfortunately, I don't have the fix right in front of me.