Restart it now.' How to FIX: Threat Service has stopped. This tutorial contains instructions to fix the following problem in Windows 10 Defender Virus & threat protection status: ' Threat Service has stopped. Restart it now.' The easy way to fix the problem, is to press the 'Restart now' button to start the threat service, but in some cases this doesn't work and you receive a new error message that says ' Unexpected error, Sorry, we ran into a problem. On a Windows 10-based computer, the Defender Antivirus Security Center may encounter the error: ' Threat Service has stopped.
