I'm trying to build a chat software. I saw a free one on the internet I want to use as a guide, the programme has compiled with no errors but when I try to build the software I have these errors,

--------------------Configuration: HyperChat - Win32 Debug--------------------
Linking...
HyperChat.obj : error LNK2001: unresolved external symbol "public: __thiscall CHyperChatDlg::CHyperChatDlg(class CWnd *)" (??0CHyperChatDlg@@QAE@PAVCWnd@@@Z)
HyperChat.obj : error LNK2001: unresolved external symbol "public: virtual __thiscall CMySocket::~CMySocket(void)" (??1CMySocket@@UAE@XZ)
nafxcwd.lib(thrdcore.obj) : error LNK2001: unresolved external symbol __endthreadex
nafxcwd.lib(thrdcore.obj) : error LNK2001: unresolved external symbol __beginthreadex
libcd.lib(crt0.obj) : error LNK2001: unresolved external symbol _main
Debug/HyperChat.exe : fatal error LNK1120: 5 unresolved externals
Error executing link.exe.

HyperChat.exe - 6 error(s), 0 warning(s)

please any help?

There is some library that your project needs to link to. Read the documentation for the downloaded code to find out which one and link it.

Regards
Ankur