Static variable usage

Dear All,
I have one doubt in static variable:-

file 1:- BSISCOOR_Coordinator_COMMON.C contains one variable
{

STATIC UWORD gs_BSISCOOR_CvrtCycCounter_UW;
}
Now i wanted to use this variable in another file. first i declared above variable in one defination file as follows:
defination file: PSWASW_CustomerSpecific_BB29047.h
{

Code:

extern UWORD gs_BSISCOOR_CvrtCycCounter_UW; }

I have included above defination file in my file2 as follows:-
file 2: - DIO_DigitalOutput_BB63215.C
{
[code]
#include PSWASW_CustomerSpecific_BB29047.h
[\code]
}

When i compile above file i am getting following error:-
i am using VC++ compiler.

### Syntax checking ..\PSW\HSW\HSW15_COMMON\BSISCOOR_COMMON\SRC\BSISCO OR_COORDINATOR_COMMON.ESC...
"..\Psw\HSW\HSW15_COMMON\BSISCOOR_COMMON\SRC\BSISC OOR_Coordinator_COMMON.ESC", line 1767: error #174-D:
external/internal linkage conflict with previous declaration
STATIC UWORD gs_BSISCOOR_CvrtCycCounter_UW;

Where i am going mistake?

Thanks in advance
Swetha