Thread: Using a dll to call a dialog in OnInitDialog of another.

I'm trying to use a dll file, I added the header file to the project put the dll and lib in the project directiory, then included the .h file but when I try to use a function I'm getting ---> TraderDialog.obj : error LNK2019: unresolved external symbol __imp__sgoCreateClientDialog referenced in function "protected: virtual int __thiscall TraderDialog::OnInitDialog(void)" (?OnInitDialog@TraderDialog@@MAEHXZ)