Dorico won't load after Noteperformer update

Dorico was fine last night, performing well. This morning after the Noteperformer update, Dorico won’t open. I get an error message about Halion 7 and VST3, but I am not sure what it is referring to.
Tried reinstalling Dorico and Halion 7, but I get the same error.
Any thoughts will be appreciated.

Edit: Tried loading Dorico 4 and it worked fine. Opened a couple of pieces in D4. All good, then went back to D5 and it loaded fine. So, this is bizarre, loading D4 fixed D5. I don’t get it! But it worked!

Noteperformer update went through fine here.

What is the exact wording of the error message?

Not necessarily!

Odd, it is now working. The earlier error messages referred to the VST 3 engine in Halion not loading, but it seems that D4 loaded them so now D5 is happy. Scratching my head on this one.