Uproject Bp when open it with UE4 editor can't see VS

hello! for me the problem is not the UE4 editor because when open UE4 standard editor or UE4 source code editor i can see vs 2017 intalled and i can create c++ class for new project but the problem when i open BP project already created before the editor ( source code or standard ) i can’t see VS and if i want create c++ class ask me for install VS 2017…anyone have solution for this issue? thank you all!