THE RESTORE SAVES THE PATH NAMES. SO EITHER USE THE TOOL AS MATT SUGGESTS OR CHANGE THE DRIVE LETTER/PATH ON YOUR NEW PC TO BE IDENTICAL TO YOUR OLD SET UP.
Now that I got that out of my system
.... So if the old computer, the xternal drive was seen as for example E:\Music and the new computer happens to be D:\Music the restore is still expecting the music to be in drive E:\. The tool is found under library tools=>Rename move copy files - option is at the top.
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