Lonks to other workbooks are not updated automatically in Excel 20
 

in one workbook other 6 workbook are linked, but the udate is not doeing it
automaticall else i have to make the update manually!
when i click Edit links from connections group in data tab, the status of
the links are shown as unknown. when i click check status the status change
to warning: values not updated.

the question is: what should i do the make the update be automatic?

thanks