Unresolved Error

While I am compiling its giving error message :

usimage.cpp
Generating Code...
Linking...
   Creating library .\Output/gci2.lib and object .\Output/gci2.exp
cam_simulator.obj : error LNK2001: unresolved external symbol _ffclos
cam_simulator.obj : error LNK2001: unresolved external symbol _ffgpxv
cam_simulator.obj : error LNK2001: unresolved external symbol _ffthdu
cam_simulator.obj : error LNK2001: unresolved external symbol _ffgisz
cam_simulator.obj : error LNK2001: unresolved external symbol _ffgidm
cam_simulator.obj : error LNK2001: unresolved external symbol _ffghdt
cam_simulator.obj : error LNK2001: unresolved external sy开发者_运维知识库mbol _ffdkopn
guide_routines.obj : error LNK2001: unresolved external symbol "float __cdecl CalcSlope(class DoubleArray)" (?CalcSlope@@YAMVDoubleArray@@@Z)
.\Release/gci2.dll : fatal error LNK1120: 8 unresolved externals
Error executing link.exe.
PixCel.exe - 9 error(s), 3 warning(s)

I changed project setting to multithreaded and liked Vfw32.lib but no change...

I am using vc++ 6.0 and xp plateform...

You are missing a library when linking, try adding the fitsio library (I believe that's what you are trying to use) to your link path.