============================================== How to reproduce

1. execute "python msvc-autogen.py"
2. open "bitcoin.sln" with VS2017
3. The project "libbitcoin_server" can not load successfully.

============================================== The reason of the problem

The file "build_msvc\libbitcoin_server\libbitcoin_server.vcxproj" has an error.

============================================== How to fix the bug

Remove the section in file "libbitcoin_server.vcxproj.in" can reslove the issue:

<ClCompile Include="..\..\src\rpc\net.cpp">
  <ObjectFileName Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">$(IntDir)\netrpc.obj</ObjectFileName>
  <ObjectFileName Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">$(IntDir)\netrpc.obj</ObjectFileName>
  <ObjectFileName Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">$(IntDir)\netrpc.obj</ObjectFileName>
  <ObjectFileName Condition="'$(Configuration)|$(Platform)'=='Release|x64'">$(IntDir)\netrpc.obj</ObjectFileName>
</ClCompile>

============================================== possible reason

I think the reason: There are two files with the same name "net.cpp", one is "src\net.cpp", the other is "src\rpc\net.cpp". There was a special section in file "libbitcoin_server.vcxproj.in" in order to produce the different obj files before. But the file "msvc-autogen.py" updated so as to process such scenario. finally, a conflict arises.

Analysis in this bug report makes sense. After 7e2e62cf7c513bd7d8e784069c5534fda1c50c52 from #14437, manually creating netrpc.obj files is unnecessary and could cause problems. Dropping the section as suggested seems like a good fix:

https://github.com/bitcoin/bitcoin/blob/fb52d0684e0f03bca5d7ddcf3fc5b0657859ac2c/build_msvc/libbitcoin_server/libbitcoin_server.vcxproj.in#L157-L162