Summary

Use the UNC Path insted of the network Drive Letter for reference:  When a reference is a added to a assembly it should store the UNC Path insted of the Mapped Drive letter

Explanation :

with network files

User(A) may have a file U:\123.sldprt in an assembly that is in a
differnt network folder and save to so user(B) and look at it
now  user(B) open the assembly but SW can't File the U:\123.sldprt because user(A) U
drive is mapped to //users/UserA/ and user(B) U Drive is mapped to //users/UserB/
if SolidWorks saved the UNC Path this would not happen

I this this will save people time when using network files with mapped drive letters

I have placed an Enhancement Request 1-1529112932