You have deklared a function but you have forgot to define the function.
For example:
Header.h:
Code:
void fuu(); //you have this
Source.cpp
Code:
void fuu() //that is what is missing... you forgot to leech this function
{
//place code here
}
SomeWhereElse.cpp:
Code:
//....
fuu(); //function is called but the Linker dont know what code he has to do if fuu() is called! => LNK2019
//....
Good Luck
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