How to fix a broken JDownloader installation
This tutorial will not fix e.g. the following issues:
- Plugin related issues (e.g. trouble downloading from a specific website or adding an account)
- Issues with your download speed
This tutorial can fix the following issues:
- Old JDownloader installation which fails to update
- FFmpeg installation inside JDownloader keeps failing over and over
- JDownloader fails to start
- JDownloader displays error Synthetica License Warning
Instructions
- Optional: Backup your accounts/downloadlist/settings
 Read the backup/restore article closely: You can backup your settings even if JDownloader fails to start!
- Close JDownloader.
- Delete these files/folders in your JD installation directory:
 Files:Core.jar, JDownloader.jar
 Folders:tmp,update
- Download the new JDownloader.jar file from here -> Choose other -> Download it and copy it in your existing JDownloader installation directory.
 Overwrite older files if your OS is asking you.
- Restart JDownloader and install all updates.
 If JDownloader still fails to start now, please contact our support!