i found that after a fresh install of xp home my D:\ drive cdrom was labled as Q:\ for some reason also.
i would try renaming it.first,make a restore point then delete the shortcut to the drive.
change it back to D:\ again by clicking:
control panel/administrative tools/computer management/disk management
right click the drive and select change drive letter and paths,rename it back to D:\ again.
create a new shortcut.