Your folder names or mapped drive letters have changed, and you want to know how to bulk change the xref paths to the DWGs (and other reference file types) stored in those network locations.
Use the Autodesk Reference Manager to modify reference paths for multiple drawings without having to open the drawings in AutoCAD.
To find the Reference Manager:
Under the Windows Start menu, search for "Reference Manager".

Do the flowing to change paths for multiple XREFs
1- Search (Reference Manager)
2- From file menu Add drawings which need to change the path
3- Select  paths which with yellow triangle then click edit selected
4-brows new path then click ok
5-click apply change.
How to change paths for multiple XREFs