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How to set Norton Security to do scans in the background and not thrash the hard drive?

Sometimes when I sit down to my computer to use it I find that Norton security is thrashing my hard drive, and my PC is unusable for 20-30 minutes until it finishes. The CPU usage isn't that high but the hard drive thrahes from Norton for about 20-30 minutes, sometimes reading disk usage as high as 90 mb/sec.

I have full system scan not scheduled and performance monitoring off. So the only scans that should be done is quick scans after a Live Update. I understand even the quick scans can take a while since my C: drive has 144 gb used out of 250 gb. So a lot to quick scan for a live update.

But how can I set Norton to scan in the background, or even idle time, even just for a quick scan after a live update?

The hard disk thrashing is annoying as my PC is unusable during the scan. I like Norton but this is really annoying. I use my PC for programming productivity so being not able to use my PC is very annoying. Please advise on how to set Norton to do scans in the background, even for manual scans, which I choose to do periodically.

If there is a setting for to do only scan in the background or idle time I have not found it yet. That setting should be prominent and easy to find, if there is one.

If idle time or background scanning is the default setting then even though Norton isn't showing too high CPU usage it is still thrashing the hard drive. If Norton is monitoring itself for CPU usage time slices for background or idle time scanning, then it should also monitor itself for disk read/writes, and throttle that as well.


Kudos1 Stats

Re: How to set Norton Security to do scans in the background and not thrash the hard drive?

Hi te7:

Check at Help | General Information | About to see if you have the latest version of Norton installed.  There was a recent product update released via Automatic LiveUpdate and it sometimes takes a few re-boots to before the update is correctly applied - see the warning at the bottom of the announcement Norton 22.9.4 Product Update available now.  Also ensure that Fast Startup (a hybrid startup similar to hybrid sleep mode in earlier versions of Windows) is disabled in your Win 10 settings as instructed in the support article Message: "You Are At Risk. Your computer and network protections are at risk".  When Fast Startup is enabled it can sometimes interfere with the loading of Norton drivers at boot-up and / or prevent the proper application of Norton updates.

Most background tasks like Quick Scans should only run when your system is idle - see the support article Monitor background jobs of your Norton service.  I occasionally see an Automatic LiveUpdate run outside of idle mode if this task hasn't run successfully for several hours, but in general background tasks should pause once you take your system out of idle (e.g., if you use your keyboard or move your mouse) and then resume once your system goes back into idle.

If you schedule a custom Quick Scan (e.g., Security | Scans | Custom Scan | Go | Quick Scan | Edit Scan) the default setting under Run the Scan should be set to Only at Idle Time by default.

The next time you notice this disk thrashing open your Norton Tasks window (Settings | Detailed Settings | Administrative Settings | Background Tasks | Configure) and see if any tasks have a Status of Running.  A task with a Status of Canceled means it was temporarily paused when your system came out of idle.  You should also monitor the Disk Usage in your Windows Task Manager as shown in the drivereasy.com article Windows 10 100% disk usage in Task Manager and confirm that your main Norton process (e.g., ns.exe, nsbu.exe) is responsible for your high disk activity.

Post back and let us know if Norton continues to thrash your hard drive outside of system idles once you've confirmed that Fast Startup is disabled and you've re-booted your system a few times to ensure the v22.9.4.8 update is installed correctly.
32-bit Vista Home Premium SP2 * Firefox ESR v52.1.2 * NS Premium v22.9.4.8


Re: How to set Norton Security to do scans in the background and not thrash the hard drive?


I don't think I would want to schedule an Idle Quick Scan. For security reasons, they should be run right after the download of the SDS Definitions. These downloads occur 2 or 3 times a day during the week and lately about 1 a day on the weekends and holidays. I can't even tell when my scans actually run.

Did you thoroughly remove the prior security program by using the Removal Tool from the previous company? Do you have any other real time security programs running currently?

You can schedule the monthly Idle Full System Scan for a time when you will not be using the computer so that it can get done in one shot/ I find it best to schedule it for overnight while I am sleeping and have nothing else scheduled at that time.


Success always occurs in private and failure in full view. Windows 10 Pro 64 bit Norton Core Security Plus Core Firmware 282 I E 11 Chrome latest version.

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