Why has Defender SmartScreen prevented an unrecognized app from starting?

You may see this warning message Microsoft Defender SmartScreen prevented an unrecognized app from starting if the antivirus software does not have the files signatures stored in its data bank. This can happen if a program executable file is new to Windows SmartScreen or if it has not been so commonly downloaded or used.

Bypass Microsoft Defender SmartScreen prevented an unrecognized app from starting

If you see this screen, the first thing you can do is click on the More info link. A new Run anyway will appear Click on Run anyway and the program will start. If you continue seeing this screen, you may need to unblock the file.

If you are sure that the file you have downloaded is safe like say our just-released Ultimate Windows Tweaker v5 – then to bypass this warning on your Windows 11 or Windows 10 computer, do the following: But after clicking the Unblock button, you will now be able to access or open the downloaded file. Similar messages you may see when a file is blocked are:

This file came from another computer and might be blocked to help protect this computer.Windows found that this file is potentially harmful. To help protect your computer, Windows has blocked access to this file.

This post will show you how to add a File or Process Exclusion to Windows Security or Microsoft Defender and this one, how to Disable SmartScreen Filter in Windows 11/10, should you wish to.

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