Evidently it must not be my lucky day. After installing Doric on the new PC and the BBCSO Core and loading the relative Dorico playback template fails to load it, exclamation marks appear next to the names of the instruments. The other Spitfire instruments I own instead appear regularly… What happened? In the vstp folder the BBCO Core dll file is missing… I guess it depends on that…
The library is installed in the same location as the others as I used an external hd to move the content to the new pc
OK, but does Spitfire know this? How does Spitfire know you have not just copied their libraries to one or more other PCs? (Just asking)
Yes I indicated the new folder, so I do not understand why it does not recognize this library… the others did not give me problems
I would ask Spitfire the question.
Hi @Fabrizio_Amapane, would you please do from the menu Help > Create Diagnostics Report and post the corresponding zip file here? Thanks
Hello! I found the solution. From the previous PC I copied the BBCSO dll file and then I copied it to the new PC in the VSTP folder. Now it works… it’s not absolutely clear to me why in copying the folder that file was lost… but I slept too few hours to understand it at this point 
… Now I just have to go ahead and reinstall Kontakt, Orchestral Tools , Engine Magix, reactivate all Ilok licenses… 
Thanks Janus and Ulf for the support. This forum never disappoints!