- Uninstall BirdieSync
- Upgrade Thunderbird and/or Sunbird if you need to.
- Install new BirdieSync version
- Launch Thunderbird or Sunbird
- Check your BirdieSync options (Thunderbird-Sunbird/Tools/BirdieSync/Options)
- Check that your BirdieSync categories (contacts, events, taks or mails) are well selected in BirdieSync Activation tab.