Oh, thanks McLabin , hope you don’t mind I call you McLabin. yes you are right, I’ve tried in this way, and I also tried to create a new C++ project by using the launcher version, then open it in my custom version. To some degree, it can work, but cannot open the c++ file from the UE directly, the connection between UE and VS is still broken. I tried compile it in another PC, also the UE4.18, while coming the same problem. Then I changed the version, I compiled UE4.16 with same step, it works… So I guess it might be the UE4.18.3’s problem. If any other guys met the same issue with UE4.18, you may try other version.