If these files are all from the same template, the range should be the same
for each file, right?

If so, you can do this: (where C4 is the cell containing the data you want
to sum):

='C:\[File1.xls]Sheet1'!$C$4+'C:\[File2.xls]Sheet1'!$C$4+'C:\[File3.xls]Sheet1'!$C$4+'C:\[File4.xls]Sheet1'!$C$4+'C:\[File5.xls]Sheet1'!$C$4+'C:\[File6.xls]Sheet1'!$C$4+'C:\[File7.xls]Sheet1'!$C$4+'C:\[File8.xls]Sheet1'!$C$4+'C:\[File9.xls]Sheet1'!$C$4+'C:\[File10.xls]Sheet1'!$C$4+'C:\[File11.xls]Sheet1'!$C$4+'C:\[File12.xls]Sheet1'!$C$4

"Shak" wrote:

i have 12 files, jan, feb, mar ............., dec. Each file is contains the
same format. Data is entered in each file monthly.

I want to creat a master file which should contain the links or fomulas to
show all the numbers of 12 files.