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Microsoft Secure

Bob writes:

My antivirus software keeps turning off and I can’t get it back on.

Here are the most common reasons you might encounter this problem:

Your computer is already infected with rogue security software

The warning that you’re antivirus software is turned off might be a fake alert, also known as “rogue security software.” This type of warning is designed to fool you into downloading malicious software or paying for antivirus software. Take our Real vs. Rogue quiz to see if you can identify the difference.”

You have more than one antivirus program

Your antivirus software could turn off if you try to install another antivirus program. Running more than one antivirus program at the same time can cause conflicts and errors that make your antivirus protection less effective or not effective at all.

You might have a virus

Some viruses can disable your antivirus software or disable updates to your antivirus software. Viruses can also prevent you from going online to update or reinstall your antivirus software.

For troubleshooting help, see What to do if your antivirus software stops working.