If a legitimate lifetime key won't activate in v5, experts recommend using the Malwarebytes Support Tool to perform a "Clean" uninstall and then reinstalling the software. Risks of "Lifetime Fixes" or Cracks
Most "cracks" and "activators" are themselves infected with trojans, miners, or spyware. By running these files, you may inadvertently grant hackers access to your personal data. malwarebytes premium v511106 fix lifetime activation