Sorry for late response. Our engineers respond:
Please let me sure just in case, have you move your database by clicking [Move Database] in [Preference] > [Advanced] > [Database] > [Database management]? From what you wrote, it might be possible that the path information in database is wrong.
And what you/we should do next is depend on what you want.
- If you simply move (not copy) the database to the external drive, we can support by sending us files and then we modify and return them back.
- If you switch library by changing external HDD, there is a way to do it: https://forums.pioneerdj.com/hc/communities/public/questions/203587223-Multiple-external-libraries-possible-
- If you duplicate your library and synchronize the libraries, unfortunately there is no certain way.
Please let us know what you want to do by moving library.