I might not be the best person to answer this because there may be an easier way. But I did this very thing awhile back and this is how.
1) In the library, choose a list which shows all the files/songs you want to change
2) Click inside that view and hit ctrl+a to select all
3) Right click and choose Library Tools -> Rename, Move & Copy Files
4) In the drop down choose "Update Databasae to point to new loction (no file rename, move, or copy)
5) Click on the Find & Replace box, making sure the Directories & Filename boxes are NOT checked
6) Enter the appropriate information into the Find What and Replace With boxes. You can enter partial information - for instance... If you moved your music from d:\music\ you'd put that into the Find What box, and if you moved your music to \\192.168.1.1\data\music\ you'd put that into the Replace With box. All instances of "d:\music\" would then be replaced with "\\192.168.1.1\data\music\" in all the library entries listed in the sub-window on the right side of the Rename, Move & Copy Files window. After you type the appropriate information into the Find What and Replace With fields you can compare the "Original" column with the "New" column to make sure the information on each entry will be changed as you wish before clicking ok to enact the changes.
BACK UP YOUR LIBRARY FIRST! It is easy to do irreparable damage with this very powerful tool... (I know from experience. /sigh)
EDIT:
If you have tagged sound files it might be easier to simply create a new library by deleting all the entries in the library as described above then use Tools -> Import to either import a single folder or set up Auto-Import for JR to continually monitor the new location for songs added. (Be sure to remove any auto-import settings which may have been set up for the old location.)
Sory for the long way first - I use untagged WAV files and tend to forget that most people use tagged files.
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Topic: New NAS Location for Libary? (Read 1644 times)