For users who cannot start trail, please advice them to do the following steps.
Open the file named "activations.xml" with Text Edit or Notepad depending of their platform.
The file is located in the folder below:
Mac: /Users/[user name]/Library/Application Support/Pioneer/rekordbox
Win: C:\Users\[user name]\AppData\Roaming\Pioneer\rekordbox
Delete two lines which start with "<init_done ..." and "<trial ...". If you don't have both lines, just delete one of them.
Make sure you input administrator's password (for Mac) / click Yes (for Win) on starting up.
If you have any information as to what might have changed on your system prior to the trial expiring, please provide those details here so the rekordbox team can investigate the cause.