This particular worklet looks for any system set to never run a full scan and changes it to run on Wednesdays. You could obviously alter it to look for a different condition and set it how you wish. For example…

You could look for systems not set to do a full scan every day in the evaluation and change it to do so…

Evaluation: if ($Preferences.RemediationScheduleDay -ne 0)

Remediation: Set-MpPreference -RemediationScheduleDay 0

Or conversely, if you want Defender to never do a full scan…

Evaluation: if ($Preferences.RemediationScheduleDay -ne 8)

Remediation: Set-MpPreference -RemediationScheduleDay 8

The acceptable values for this parameter are:

• 0: Everyday


• 1: Sunday


• 2: Monday


• 3: Tuesday


• 4: Wednesday


• 5: Thursday


• 6: Friday


• 7: Saturday


• 8: Never

Evaluation:

# Determine if full Defender scans are set to never run

$Preferences = Get-MpPreference

if ($Preferences.RemediationScheduleDay -eq 8)

    { exit 1 }

else

    { exit 0 }

Remediation:

# Set a full Defender scan to run on Wednesdays

Set-MpPreference -RemediationScheduleDay 4