Windows Defender Full Scan

How long does it typically take Windows Defender to conduct a full scan?
 

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Last updated November 12, 2019 Views 6,288 Applies to:
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If you're running a Full scan for the first time, it may take several hours to complete, depending on your settings.

Full scan has been running for over. 20 hrs and is not even 50% complete. Nothing is running in the background. If this is their best effort it sucks!  Now what do I  do? And am I protected?

Things to consider when your Full Scans seem outrageously long:

Full Scans are paused when the System idles to sleep (after 30 minutes by default), and are not resumed until you wake up your PC:

https://answers.microsoft.com/en-us/protect/forum/protect_defender-protect_scanning/defender-full-scan-still-running-after-22-hours/cb69f242-a673-4dee-837d-317785a1b57a

https://answers.microsoft.com/en-us/protect/forum/protect_defender-protect_scanning/how-can-i-run-windows-defender-walk-away-and-have/7b57798e-b2da-40a6-9c74-afd9ff2dff11

https://answers.microsoft.com/en-us/protect/forum/protect_defender-protect_scanning/how-do-i-do-a-set-and-forget-full-scan-with/a1fb5e32-f227-42b6-b455-05ae41f40bf6

https://answers.microsoft.com/en-us/protect/forum/protect_defender-protect_start/initial-scan-with-windows-defender-in-windows-10/eb9efd51-7a74-4f50-8a40-9cde2db5c25c

Running Quick Scans or Custom Scans will help build up Defender’s cache of trusted files and shorten up your Full Scans when the cache is reset by an OS Update:

https://answers.microsoft.com/en-us/protect/forum/protect_defender-protect_scanning/windows-10-1511-10586-windows-defender-full-scan/436b7fd5-8e87-46c4-99fa-db4a0cf09fc1

https://answers.microsoft.com/en-us/protect/forum/protect_defender-protect_scanning-windows_10/wd-scan-still-running-after-more-than-10-hours/4d34fbbc-c459-46b4-8378-8bc9843420a7

Scans will be slowed (and CPU utilization will be elevated) by any other real-time security app, or remnants thereof. Make sure that you’ve run the cleanup utilities for any previously installed, or preinstalled, AV apps:

https://answers.microsoft.com/en-us/protect/forum/mse-protect_start/list-of-anti-malware-product-removal-tools/2bcb53f7-7ab4-4ef9-ab3a-6aebfa322f75

Uninstalling unused programs, deleting unused files, and using Disk Cleanup will reduce the workload for your scans and shorten their run times.

In addition to physically removing files, you can further reduce the scan’s workload by excluding files. You can add your personal work files, media files, archived backups, disk images, etc., to the list of trusted files simply by creating either path or type exclusions for them:

https://support.microsoft.com/en-us/instantanswers/64495205-6ddb-4da1-8534-1aeaf64c0af8/add-an-exclusion-to-windows-defender

Turning off Archive Scanning will exclude most types of archive files in one simple step, and it will have a pronounced effect on the run times for your Full Scans:

https://answers.microsoft.com/en-us/protect/forum/protect_defender-protect_scanning/how-can-i-exclude-archive-files-for-a-scan-in/2d515e9d-a0cb-4759-8cb5-9fd7f5cc84ca

GreginMich

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