Updating links
 

I selected to update the links when I open my spreadsheet, because I was
given a new worksheet to link to (so i just renamed this new sheet
LINKEDsheet as before, and saved the old linked sheet under a new name
LINKEDsheet1)
The new information shows up, but after 2 minutes the numbers magically
change back to the old sheet's values...

How can this happen if my workbook is no longer linked to the old info, and
how can i prevent this from happening???

***I was told that if the LINKEDsheet is open, the update stays current, but
if it's not open, it will magically change back...***