Sorry for my not very good english

I have several files that have linked call to a woorkbook.

ES: in the cells there are formulas like that

='\\Server2003\Dati\PRODOTTI\myfolder\[linkedfile.xlsm]sheet1'!B14

Server2003 is a folder on server.



I have set in my computers to not refresh cells from llinked files, so they don't open linked files but they refresh only when I open both files at the same time



My problem is:
I don't know why sometimes (1:10000 times) the links change to
='\\Server2003\PRODOTTI\myfolder\[linkedfile.xlsm]sheet1'!B14

the folder Dati disappears from formulas, so the file became inusable