indexing not working on URL path

When entering a share where Serviio can find photos or music, there is nothing found by several client systems. If I change the URL path to a driveletter/foldername, everything works fine. \\sbs2008\song$ does not work while M:\SONG does.
I prefer to enter URL path instead of a reserved driveletter.
Only domain users and domein admins can access the shared folers.
Is there something going wrong?

I prefer to enter URL path instead of a reserved driveletter.
Only domain users and domein admins can access the shared folers.
Is there something going wrong?