I am going to assume you are building a RFA C++ 8.2.0.L2.static application.
Are you building one of the existing examples or your own application?
If you are building your own application please ensure the wininet.lib library is included in your project settings for Linker->Input->Additional Dependencies.
e.g. for the StarterConsumer example I can see the following specified:
msvcprtd.lib;msvcrtd.lib;ws2_32.lib;wininet.lib; libRFA8_140_x64.lib; %(AdditionalDependencies)
If I remove wininet.lib, then I also get
Error in linking:
libRFA8_140_x64.lib(ripcinetutils.obj) : error LNK2019: unresolved external symbol __imp_InternetOpenA referenced in function ripcWinInetConnect
libRFA8_140_x64.lib(ripcinetutils.obj) : error LNK2019: unresolved external symbol __imp_InternetCloseHandle referenced in function ripcReleaseWinInetSession
libRFA8_140_x64.lib(ripcinetutils.obj) : error LNK2019: unresolved external symbol __imp_InternetConnectA referenced in function ripcWinInetConnect
libRFA8_140_x64.lib(ripcinetutils.obj) : error LNK2019: unresolved external symbol __imp_InternetReadFile referenced in function ripcWinInetInitConnection
libRFA8_140_x64.lib(ripcinetutils.obj) : error LNK2019: unresolved external symbol __imp_InternetWriteFile referenced in function ripcWinInetInitConnection
libRFA8_140_x64.lib(ripcinetutils.obj) : error LNK2019: unresolved external symbol __imp_InternetQueryDataAvailable referenced in function ripcWinInetConnect
libRFA8_140_x64.lib(ripcinetutils.obj) : error LNK2019: unresolved external symbol __imp_InternetSetOptionA referenced in function ripcWinInetConnect
libRFA8_140_x64.lib(ripcinetutils.obj) : error LNK2019: unresolved external symbol __imp_InternetSetStatusCallback referenced in function ripcReleaseWinInetSession
libRFA8_140_x64.lib(ripcinetutils.obj) : error LNK2019: unresolved external symbol __imp_HttpOpenRequestA referenced in function ripcWinInetConnect
libRFA8_140_x64.lib(ripcinetutils.obj) : error LNK2019: unresolved external symbol __imp_HttpSendRequestA referenced in function ripcWinInetConnect
libRFA8_140_x64.lib(ripcinetutils.obj) : error LNK2019: unresolved external symbol __imp_HttpSendRequestExA referenced in function ripcWinInetInitConnection
libRFA8_140_x64.lib(ripcinetutils.obj) : error LNK2019: unresolved external symbol __imp_HttpEndRequestA referenced in function ripcWinInetRead
libRFA8_140_x64.lib(ripcinetutils.obj) : error LNK2019: unresolved external symbol __imp_InternetAttemptConnect referenced in function ripcWinInetConnect