To update your track collection in Traktor, you can do the following:

1. find out where the music files you want to update are actually located on your hard drive.

2. once you locate them, then use the browser in Traktor to point directly to these files. Using the "explorer" section of the browser allows you to navigate your hard-drives and files/folders just like Windows Explorer does.

3. once you find the files within the Traktor browser, simply drag the entire folder into the "track collection" in the Traktor browser, and Traktor will add this to your existing collection database.