In the first public release of Windows 10, Microsoft took some hits from antivirus vendors who were concerned that the free Windows Defender would hamper their ability to generate revenue in the security market.
When Windows 10 Anniversary Edition is available at the end of July, the OS update will include a new Windows Defender scanning feature called, Limited Periodic Scanning.
Limited Periodic Scanning is a new feature that restricts scanning to longer interval schedules. This allows 3rd party antivirus solutions to work without constantly conflicting with the on built into Windows 10. Windows Defender today provides near real-time system scanning. Giving Windows Defender the capability to run periodically allows it to become a sort of backup to other modern antivirus products.
Microsoft has noted through the telemetry from its Malicious Software Removal Tool scans that 3rd party antivirus solutions miss detection. So, customers can now opt to choose a 3rd party security solution, but also feel comfortable that if their choice fails, Microsoft is there to ensure they are safe anyway.
Limited Periodic Scanning will come turned off by default in Windows 10 Anniversary Edition. If you notice scanning conflicts between Windows Defender and a 3rd party antivirus solution after upgrading to Windows 10 Anniversary Edition, you’ll want to turn this one.
Obviously, if you feel you only need Windows Defender to do the job, you can leave this feature turned off.