Problems building .Net application with a reference to 3cxpscomcpp2.dll

[ubsysteme.de]

Hello,

I have problems building a .Net application with a reference to 3cxpscomcpp2.dll.
I have read that the output directory of my build must be the 3CX installation directory.
But if I build my application into this directory I get the following error message:

"C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\MSBuild\Microsoft\Microsoft.NET.Build.Extensions\net461\lib\System.Net.Http.dll" konnte nicht in "..\..\..\..\..\..\..\Program Files\3CX Phone System\Instance1\Bin\System.Net.Http.dll" kopiert werden. ...

My Setup:
- Visual Studio Community 2017 Version 15.7.3
- .Net Framework 4.6.1
- 3CX V 15.5

Steps to reproduce:
- Create a new Application (WindowsForm or Console)
- Add a reference to c:\Program Files\3CX Phone System\Bin\3cxpscomcpp2.dll
- Change output directory to C:\Program Files\3CX Phone System\Instance1\Bin
- Build project -> Error Message

If I don't change the output directory I get the error
"Unable to load DLL 'tcxpscom_native': The specified module could not be found. (Exception from HRESULT: 0x8007007E)"

What are the best settings for debugging an .Net application for 3CX?
Should I always shutdown the 3CX service while building my application?

Regards
M. Pannier