One of the most important files used by your Serato software is the database V2 file. This is stored in the _Serato_ folder in the Music folder on your internal hard drive, and in the _Serato_ folder on any partitions and external hard drives that your Serato software has accessed.
The database V2 file stores your library information such as whether a track has been played, whether a file has had its overview built, which tracks are corrupt, which tracks are from your iTunes library and much more.
Unfortunately sometimes this file can become corrupted, and you may notice odd behavior with your library. Symptoms of a corrupt database can be blue/grey "played" files not saving or ID3 tags being re-read every time on startup. Creating a new database V2 will fix this and is easy to do.
Note: Rebuilding the databaseV2 file will revert all of the 'date added' dates to today's date and will delete any files out of your Serato software that aren't currently in a crate or playlist.
Following are the steps to create a brand new database V2 file.
1) Open your Serato software.
2) Create a new crate and name it whatever you like (for the sake of this article we'll call it "BACKUP ALL")
3) Click on the "All..." crate at the top of your crates list. This will now display all the files in your library in the Main Library Track List.
4) Click in the Main Library Track List and press Ctrl + A to highlight all tracks.
5) Click and drag all the files from your Main Library Track List into the backup all crate. This crate will now contain every song in your library.
6) Close your Serato software.
7A) If on a PC: Open Explorer and go to My Music -> _Serato_
7B) If on a Mac: Open Finder and go to Music -> _Serato_
In here you will see your database V2 file. Rename it to something else (eg. "database V2 backup"), in case you need to restore it.
If you have any partitions or external hard drives there will be a folder on these called _Serato_ which also contains a databaseV2 file. Repeat this step for these files too.
8) Reopen your Serato software. As you have renamed your original database V2 file, your Serato software won't be able to find it, so it will create a new one. It will populate it with all the tracks that are in your crates. As we created a crate earlier containing all of your files these will be added to the new database V2 file.
Voila! You now have a new, clean and uncorrupted database. You can now delete the "backup all" crate by selecting it and pressing control + delete (Note: the crate will be deleted but the files will remain).