Qt Unresolved external symbol QMetaObject error

This one was incredibly frustrating as a Qt noob...

Error   4   error LNK2001: unresolved external symbol "public: virtual struct QMetaObject const * __thiscall Counter::metaObject(void)const " (?metaObject@Counter@@UBEPBUQMetaObject@@XZ) 

Error   5   error LNK2001: unresolved external symbol "public: virtual void * __thiscall Counter::qt_metacast(char const *)" (?qt_metacast@Counter@@UAEPAXPBD@Z)

Error   6   error LNK2001: unresolved external symbol "public: virtual int __thiscall Counter::qt_metacall(enum QMetaObject::Call,int,void * *)" (?qt_metacall@Counter@@UAEHW4Call@QMetaObject@@HPAPAX@Z)  

Error   7   error LNK2019: unresolved external symbol "protected: void __thiscall Counter::valueChanged(int)" (?valueChanged@Counter@@IAEXH@Z) referenced in function "public: void __thiscall Counter::setValue(int)" (?setValue@Counter@@QAEXH@Z

This happens when you use the Q_OBJECT macro in your class extending QObject. Turns out in Qt you need to call run qmake first in order to invoke the moc compiler. So, the proper solution: 1. Run qmake 2. Build 3. Run