unresolved-external

I must be missing a basic concept with headers and includes because when I attempt to call even the simplest of a function from a separate source file I get an error: main.obj:-1: error: LNK2019: unresolved external symbol "void __cdecl buildDeck(int,int)" (?buildDeck@@YAXHH@Z) referenced in function _main deck.h #ifndef DECK_H #define DECK_H #include <QString> void buildDeck(int deckSize, int jokers); struct card { QString suit; QString color; int rank; }; #endif // DECK_H deck.cpp #include"mainwindow.h" #include "deck.h" void buildDeck(int deckSize, int jokers) { int blackRed = deckSize-

I am quite new to C++ so I downloaded a sample C++ program. The sample program seems to hit the following error when it is compiling :- Error 22 error LNK2019: unresolved external symbol _acsEnumServerNames@12 referenced in function "protected: virtual int __thiscall COpenTsrv::OnInitDialog(void)" (?OnInitDialog@COpenTsrv@@MAEHXZ) Opentsrv.obj I traced it to the referred function but I do not know anything wrong with it ? BOOL COpenTsrv::OnInitDialog() { CDialog::OnInitDialog(); CenterWindow(); acsEnumServerNames(ST_CSTA, AddToList, (unsigned long) (CComboBox*)&m_TserverListControl);

I have tried this code in a totally separate project, and it works fine (the only difference being that the project that is not working is being exported as a DLL). Here is the code: RTATMATHLIB.CPP #include "stdafx.h" #include "RTATMATHLIB.h" #include <math.h> #include <vector> #include <algorithm> #include <stdexcept> using namespace std; double someFunc(double** Y, int length) { vector<double> myVector; for(int i = 0; i < length; i++) { double value = (*Y)[i]; vector<double>::iterator it = find(myVector.begin(), myVector.end(), value); if(it != myVector.end()) { continue; } else { myVector

I know this is programming questions but I'm just frustrated trying to figure out what I'm doing wrong.. I'm using visual studio 2010 and followed all the steps here: http://curl.haxx.se/libcurl/c/visual_studio.pdf When I try to compile my solution I keep getting this error: 1>------ Build started: Project: LibCurl, Configuration: Debug Win32 ------ 1>LibCurl.obj : error LNK2019: unresolved external symbol __imp__curl_easy_cleanup referenced in function _main 1>LibCurl.obj : error LNK2019: unresolved external symbol __imp__curl_easy_perform referenced in function _main 1>LibCurl.obj : error

During coding in Visual Studio I got an unresolved external symbol error and I've got no idea what to do. I don't know what's wrong. Could you please decipher me? Where should I be looking for what kind of errors? 1>Form.obj : error LNK2019: unresolved external symbol "public: class Field * __thiscall Field::addField(class Field *)" (?addField@Field@@QAEPAV1@PAV1@@Z) referenced in function "public: void __thiscall Form::parse(class std::basic_stringstream<char,struct std::char_traits<char>,class std::allocator<char> > &)" (?parse@Form@@QAEXAAV?$basic_stringstream@DU?$char_traits@D@std@@V?