[c++]Linker Problems

[PsyChiC]

I want to compile my project but i get this error

error LNK2001: unresolved external symbol "unsigned long __cdecl Intercept(int,unsigned long,unsigned long,int)" (?Intercept@@YAKHKKH@Z)

error LNK2001: unresolved external symbol "void __cdecl MyThread(void *)" (?MyThread@@YAXPAX@Z)