When you suspect that a file or a program is malicious, you can send the file to the Microsoft Research and Response team for analysis. Malicious files or programs (malware) may include viruses, spyware, worms, and adware.

Find out what to do if your game crashes because of your antivirus software on Windows 10.

Here's how to do that on Windows, Mac, or Android.

Microsoft Defender Offline will load and perform a quick scan of your PC in the Windows Recovery Environment. When the scan completes, your PC automatically restarts. Note: To see the results of the offline scan, open the Windows Security app on your Windows device and select Protection history.

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During a scan, Microsoft Safety Scanner detects possible malicious software contained in a file archive, such as a .zip file. You should determine whether the file is malicious software and remove it from the archive manually. To determine whether the file is malicious, follow the steps below:

Microsoft does not send unsolicited email messages or make unsolicited phone calls to request personal or financial information, or to provide technical support to fix your computer. If you didn't ask us to, we won't call you to offer support. If a pop-up or error message appears with a phone number, don’t call the number.

Get Help has troubleshooters you can run for many common scenarios. These often help resolve issues without the need to contact support. If a troubleshooter is available for your issue, select Start to run that troubleshooter. After you run any troubleshooter, Get Help provides details on any findings and suggestions for possible remedies.

There are several ways to send and receive a blocked file. You can save the file to the cloud and send a link to the file, use a file compression utility like WinZip, or even rename the file with another extension, then have your recipient change the name back to the original name after they receive the file.

Windows 11 might shut down or restart unexpectedly when a serious problem occurs, causing you to briefly see an error message, such as “Your device ran into a problem and needs to restart.” Windows 11 will then restart automatically.