won't automatically scan

Question

Defender has quit automatically running quickscan. How do I get it to automatically scan?

Answer 1

There’s an issue with Version 1607 that causes the Windows Defender Scheduled Scan task to fail quite consistently. The failure is immediate:

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MpCmdRun: Command Line: "C:\Program Files\Windows Defender\MpCmdRun.exe" Scan -ScheduleJob

 Start Time: ‎Mon ‎Oct ‎17 ‎2016 10:51:04

Starting RunStartStart: IdRunCommandScan is using default scan type: 1.

Scanning path as file: (null).

Start: MpScan(MP_FEATURE_SUPPORTED, dwOptions=16385, Timeout in days = 1)

MpScan() started

MpScan() was completed

ERROR: MpScan(dwOptions=16385) Completion Failed 80508018

MpCmdRun: End Time: ‎Mon ‎Oct ‎17 ‎2016 10:51:04

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And is limited to the scheduled scan task:

There are several viable options for dealing with this issue:

1. Just ignore the problem and wait for a fix (there’s little to no risk involved in relying solely on Defender’s real-time protection).

2. Run manual scans occasionally.
3. Schedule a scan with the Create Basic Task Wizard that runs under the (default) local administrator account:

http://answers.microsoft.com/en-us/protect/forum/protect\_defender-protect\_scanning/automatic-update-broke-windows-defender/fad7be45-cf9e-4e5c-a6cd-cf2c2d83c345

4. Change the user account for the Windows Defender Scheduled Scan task (the scheduled task that’s run by Automatic Maintenance) to the local administrator – exactly as described here:

http://answers.microsoft.com/en-us/protect/forum/protect\_defender-protect\_scanning/windows-defender-daily-quick-scan-windows-10-os/af9b6bf8-7880-48c1-afde-4043534b55d3

If your PC isn’t password protected, then first change the account to the local administrator, and then check the Do not store password. The task will only have access to local resources option.

GreginMich