BitDefender Threat Scanner Error

Updated on Feb 24, 2026

If your Defender device with BitDefender Antivirus prompts the a "BitDefender Threat Scanner" error message like the one displayed below, please do the following to resolve this issue.

BD_ThreadScanner.png

Option 1:

  • Physically disconnect the USB device from the USB port and attempt to log back into the device.
  • If possible, the device will re-download the AV definition files.
  • If this does not resolve the problem, proceed with option 2 below.

 

Option 2:

  • Once the above error occurs, click the OK button.
  • Navigate to the secure partition of the Defender device.
  • Locate the folder titled "SYSTEM" (Note: This is a hidden folder, so you must have the show hidden files and folders enabled within Windows)
  • Only delete the contents of the folder titled "Plugins" as shown below. This is the folder that contains the antivirus definitions.
  • Physically disconnect the Defender device once complete and reconnect/login to your device.
  • The AV files will be re-downloaded.

BD_AV_SYSTEM_Plugins.png