To repair your Bitdefender 2015 product follow these steps:
1. Press the Windows Key and the R key together on your keyboard.
2. Type appwiz.cpL in the command box that appears and press Enter.
3. This will bring up Programs and Features in Control Panel. Locate the Bitdefender product in the list, right click on it and choose Uninstall.
4. A wizard will appear. Choose Repair. Wait for the process to complete and then restart your computer for the changes to take effect.