Undefined symbols on creating debugging DLL-phase?

[kn]

I have a problem in creating debugging DLL phase. The problem is that I always get error messages about undefined symbols on a .c file.
These commands, that making these errors are described in a header file:
extern __declspec(dllimport)int WINAPI setup (int , int , int );
extern __declspec(dllimport)int WINAPI sendaddress (int, int, int);
extern __declspec(dllimport)int WINAPI writebyte(int, int);
extern __declspec(dllimport)int WINAPI readbyte(int, int);
extern __declspec(dllimport)int WINAPI sendstop(int);
extern __declspec(dllimport)int WINAPI restart (int, int, int);
extern __declspec(dllimport)int WINAPI getstatus(int);
extern __declspec(dllimport)int WINAPI recover(int);
extern __declspec(d
llimport)int WINAPI slavelastbyte(int);
extern __declspec(dllimport)int WINAPI dllissue(void);

Is there something wrong or where the error is?

[Pierre_63]

Where did you get this message ?.When creating the dll or when using it.

If it's when you try to use it you have probably forgotten to include the prototype file when creation your dll : In your dll project : see "Buil<<