unresolved external symbol error

See more:

VisualC++

HI All

I have code in vc++ i converted this code from c to object orinted vc++.
My problem is this that i coverted the code finely in vc++.
by making the .c files into .cpp files and in the header files
i put all the functions inside a class .
and conert all the global static variables into local variable
then creting objects of header files classes and access the function hwere ever they are used .
At this place after conversion in object orintation my code works fine for multi threading application
..
Now my problem is this when i create the DLL file of that code which works fine it give me this error on function .

abc_ana.obj : error LNK2001: unresolved external symbol "public: double __thiscall vq_lib::vq_enc(double *,double *,int,int,double *,int *)" (?vq_enc@vq_lib@@QAENPAN0HH0PAH@Z)
abc_ana.obj : error LNK2001: unresolved external symbol "public: int __thiscall lpc_lib::lpc_lsp2pred(double *,double *,int)" (?lpc_lsp2pred@lpc_lib@@QAEHPAN0H@Z)
abc_ana.obj : error LNK2001: unresolved external symbol "public: double __thiscall vq_lib::vq_ms4(double *,double *,double *,int *,int,int,int,double *,double *,int *,int)" (?vq_ms4@vq_lib@@QAENPAN00PAHHHH001H@Z)
abc_ana.obj : error LNK2001: unresolved external symbol "public: double * __thiscall vq_lib::vq_lspw(double *,double *,double *,int)" (?vq_lspw@vq_lib@@QAEPANPAN00H@Z)
abc_ana.obj : error LNK2001: unresolved external symbol "public: int __thiscall lpc_lib::lpc_clmp(double *,double,int)" (?lpc_clmp@lpc_lib@@QAEHPANNH@Z)
abc_ana.obj : error LNK2001: unresolved external symbol "public: int __thiscall lpc_lib::lpc_pred2lsp(double *,double *,int)" (?lpc_pred2lsp@lpc_lib@@QAEHPAN0H@Z)
abcp_ana.obj : error LNK2001: unresolved external symbol "public: int __thiscall lpc_lib::lpc_bwex(double *,double *,double,int)" (?lpc_bwex@lpc_lib@@QAEHPAN0NH@Z)
abc_ana.obj : error LNK2001: unresolved external symbol "public: double __thiscall lpc_lib::lpc_schr(double *,double *,double *,int)" (?lpc_schr@lpc_lib@@QAENPAN00H@Z)
abc_ana.obj : error LNK2001: unresolved external symbol "public: void __thiscall vq_lib::vq_fsw(double *,int,double)" (?vq_fsw@vq_lib@@QAEXPANHN@Z)
abc_ana.obj : error LNK2001: unresolved external symbol "double * abc_cb" (?msvq_cb@@3PANA)
abc_chn.obj : error LNK2001: unresolved external symbol "double * abc_cb" (?msvq_cb@@3PANA)
abc_chn.obj : error LNK2001: unresolved external symbol "public: double * __thiscall vq_lib::vq_msd2(double *,double *,double *,double *,int *,int *,int,int,int)" (?vq_msd2@vq_lib@@QAEPANPAN000PAH1HHH@Z)
abcMain.obj : error LNK2001: unresolved external symbol "public: void __thiscall melp1::melp_syn(class melp_param *,double * const,double *,double *,double *,int *,int *,double *,double *,double *,class melp_param *,double *,double *,double *,doubl
e *,double *,double *,struct msvq_param *,struct msvq_param *,double *,double *)" (?abc_syn@melp1@@QAEXPAVmelp_param@@QANPAN22PAH32220222222PAUmsvq_param@@422@Z)
abcMain.obj : error LNK2001: unresolved external symbol "public: void __thiscall melp1::melp_syn_init(double *,double *,double *,int *,int *,double *,double *,double *,class abc_param *,double *,double *,double *,double *,double *,double *,struct
msvq_param *,struct msvq_param *,double *)" (?abc_syn_init@melp1@@QAEXPAN00PAH1000PAVabc_param@@000000PAUmsvq_param@@30@Z)
Debug/MelpDLL3.dll : fatal error LNK1120: 13 unresolved externals

plz help

How to get out of this error while creating Dll