Force External Reference to Same Path

Using Excel 2010. Original user creates an external reference in a cell in the destination workbook to the source workbook using the absolute path on a mapped network drive (u:\folder\subfolder\filename). Other users access same destination workbook, and sometimes when the original user opens the destination workbook, the path is updated to a different absolute path (for example, u:\subfolder\filename).

How can a user force the external reference to use the same absolute path no matter who opens or how the file opened?