Solved Should You Run System File Checker (SFC) Periodically?

I am not sure that I am posting this thread in the correct location. If appropriate, please move it.

Out of curiosity, should you run the System File Checker (SFC) periodically, say quarterly, or just when you run into difficulties?

I noticed Eleven Forums has a tutorial located here: Use System File Checker (SFC) to Repair System Files in Windows 11 Tutorial

If I were to use SFC on a quarterly basis, I would likely use Option 1.

Browsing on the internet, I found a slightly different protocol: Using System File Checker in Windows - Microsoft Support

It seems the steps are as follows:

1. Make sure that the computer is updated before proceeding
2. Run the elevated command prompt as administrator:
   1. DISM.exe /Online /Cleanup-image /Restorehealth followed by
   2. sfc /scannow

My questions are as follows:

• Do you run SFC periodically as a preventative measure, or what are best practices?
• Would you recommend Option 1 in Eleven Forums tutorial, or the slightly longer "internet" version? And how did you decide between those two options?

I run SFC after each Patch Tuesday (or any update), then if SFC finds anything (fixed or not)... I run DISM.

If you intend to run DISM first, reboot afterwards, then run SFC. If you don't reboot... SFC will take forever.
If you run SFC first, then you can (if desired) run DISM without rebooting.

You only need to repair Windows system files when there is problem with it executing SFC or Dism when there is no problem to repair is a waste of your time.

@Ghot, thank you for your reply.

I like your approach and may adopt it myself. In a discussion with a technician from the manufacturer, he mentioned that he does not use TRIM. Instead, he tends to rely on System File Checker. I did not ask how frequently he uses it or his general process. Although I like using TRIM, his comment made me think if I was missing something.

Stecyk said:

@Ghot, thank you for your reply.

I like your approach and may adopt it myself. In a discussion with a technician from the manufacturer, he mentioned that he does not use TRIM. Instead, he tends to rely on System File Checker. I did not ask how frequently he uses it or his general process. Although I like using TRIM, his comment made me think if I was missing something.

Click to expand...

I manually run TRIM about every 60-90 days.

@FreeBooter, thank you for your reply.

Yes, there is certainly an argument for doing nothing until necessary. I am curious if there is a best practices or how most others use System File Checker.

Ghot said:

I manually run TRIM about every 60-90 days.

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I have set up my three drives to run TRIM weekly. It's sort of a set-it-and-forget-it approach.

On my old computer, I used to use Intel's utility software to manually run TRIM every weekend. It mentioned that TRIM should be done weekly, so I have decided to keep that frequency with my new computer.

I only run sfc when I think there's a need to as it will always show an error and to reboot for the fix. This is because I run Stardock's Icon Packager. Don't like the default folders icon in Win 11.
If sfc shows it can't fix an error then I'll reboot and run DISM followed by sfc.

Trim is set like yours, set and forget.

I run SFC only if I have a problem. I image my OS drive every month after patch Tuesday, more often if I make a lot of changes to the OS. But about every 6 months, I will run SFC before I make that month's image. I keep it as what I call my master image until 6 months later when I run SFC again and replace it with a new master image. When I make a master image, I immediately restore that image to make sure it is viable. For all the monthly images inbetween, I verify them but do not test that they will restore. None have ever failed me, though. I never rely on having just one image nor do I have all the images on one storage drive. At any given time, I will have 8. One made when the computer was new, one made before the last version update, a master image and 5 monthly images. I figure that should cover all my bases.

I used to run all sorts of checks regularly, including daily malware checks. Since Windows 10 I stopped bothering - unless I have an issue.

Trim is nothing to do with SFC, they perform very different functions so not sure why your 'technician' made some correlation there.
SFC is useful to run if you notice issues, like apps suddenly not launching, permissions on files/ folders not being correct etc.

Trim forces the drive to attempt to clear blocks marked for deletion on the SSD, depending on the drive activity and the firmware construction TRIM may not run at all when called (the command will complete but no actual changes are made) you can see this if you run TRIM with PowerShell and the verbose switch, for example : Optimize-Volume -DriveLetter C -Analyze -Verbose

The operating system sends a TRIM command when writing to the drive, but it is up to the drive as to when to execute TRIM in that case (the manual TRIM is actually RE-TRIM).

As to when to use TRIM it is a good idea to run it according to the drive usage, lots of activity run it more often (weekly is fine), less activity monthly or longer could be fine (think a game drive where there are few writes such as updates, saved game data etc.).
SFC use if issues are encountered and/ or after a Windows update, cumulative for example.

Be careful with DISM cleanup, reset commands they will often remove the ability to undo an update as well as remove the update from the cache folder.

Thats my view of using these commands and method.

Windows does automatic TRIM weekly by default: Retrim Drives in Windows 11

In a parallel thread that I can't find right now, @Ed Tittel pointed out MS' peculiar recommendation to fist run DISM /Online /Cleanup-image /Restorehealth followed by sfc /scannow

Makes me wonder if it is the DISM command (and not sfc /scannow) that should be run like one is taking one's vitamins.

Haydon said:

In a parallel thread that I can't find right now, @Ed Tittel pointed out MS' peculiar recommendation to fist run DISM /Online /Cleanup-image /Restorehealth followed by sfc /scannow

Makes me wonder if it is the DISM command (and not sfc /scannow) that should be run like one is taking one's vitamins.

Click to expand...

sfc /scannow is faster, but dism /online /cleanup-image /checkhealth should be run always first if the goal is to gather information to be able to diagnose what might be causing the corruptions in question. dism /online /cleanup-image /restorehealth is not needed after sfc /scannow reported no corruptions or after it reported that it successfully repaired them, so trying sfc /scannow always first will usually help you save time because usually it will succeed, and when it does, then dism /online /cleanup-image /restorehealth will not be needed. sfc /scannow is much faster than dism /online /cleanup-image /restorehealth, but in the rare event that sfc /scannow reports corruptions and was unable to fix them, you'll still need to run dism /online /cleanup-image /restorehealth. But this happens only very rarely so that's why I prefer to just run the sfc /scannow always first. Who needs to gather diagnostics info when everyone already knows that the problem is called Botch Tuesdays.

I had run SFC at least 3 times since I clean installed W11 Pro about 2 months ago. Each time it came up with integrity violations.
Today I just did DISM /Restorehealth first - it was stuck at 62.3% for a while then finished successfully.
Then ran SFC - no integrity violations.

TVeblen said:

I had run SFC at least 3 times since I clean installed W11 Pro about 2 months ago. Each time it came up with integrity violations.
Today I just did DISM /Restorehealth first - it was stuck at 62.3% for a while then finished successfully.
Then ran SFC - no integrity violations.

Click to expand...

Often those integrity violations are simple duplicate permissions set for Windows folders/ files and are not actual corruption of/ missing system files.

Going back a few posts in this message, I just wanted to provide a little clarification on the topic of running TRIM.

In a perfect world, you would NEVER need to run TRIM manually or on a scheduled basis, because TRIM runs automatically every time a block of data is deleted on the SSD.

However, we don't live in a perfect world. In real life, here is just one example of the kind of thing that can happen:

A large amount of data can get deleted which causes TRIM to take a long time to complete, during which time the system is rebooted or shutdown, resulting in pending TRIM operations not being completed.

So, when an optimization is kicked off manually or via the schedule for doing so, Windows is simply providing "hints" to the SSD, telling it what blocks it sees as being unused. The SSD then looks at all those blocks to see if they have already been TRIMed, and if any blocks have not been TRIMed, it will perform a TRIM operation on them at that time.

As was noted, TRIM is something very different than SFC. TRIM does not care one bit about the validity or integrity of your data. It's sole reason for living is to ensure that unused blocks on the SSD are erased. With a HDD, if you want to write data to previously used blocks, there is absolutely no difference than writing to blocks that were never used before; you simply write your data to that block and you are done. With an SSD, any block that previously had data on it must first be erased before new data can be placed into that block. In fact, it gets even worse: Even if you want to alter only a single byte of data in a block, you first need to read the contents of the block, erase it, then re-write the entire block of data along with the changes. That process can DRAMATICALLY slow down an SSD, hence the need for TRIM to avoid that scenario. With a properly TRIMed drive, any new writes to the SSD will go to blocks that have already been erased, ensuring that maximum performance is achieved.

Hope this helps to clarify what TRIM is actually doing.

BruceR said:

Windows does automatic TRIM weekly by default: Retrim Drives in Windows 11

Click to expand...

Thank you for your comment, @BruceR.

Your link certainly indicates what you say is true. I have one observation and one question, though.

My new computer is about a month old. When I ventured into this area, I noticed that my C drive had not been TRIMMed for 31 days. If Windows does this automatically, then why has the C drive not been TRIMMed?

My question is, Why is one of the scheduled options one month? If drives are trimmed every ten days at most, then what's the purpose of having a monthly option?

I want to thank those who responded:

@Fabler2 Thank you for your comment.

@glasskuter I admire your organized approach.

@Hazel123 There is something to be said for just addressing issues as they arise.

@DigitalGoat Agreed that SFC and TRIM are different beasts. I suspect the technician was like many here that tend to address issues when they arise. He might occasionally run SFC. But he deemed it unnecessary.

@Haydon You may want to refer to @Ghot's comment regarding the sequence. Ghot stated that if DISM is run first, one should reboot before running SFC. Thank you for your comment.

@hdmi Your second link confused me because you began talking about defrag. As far as I know, when you hit Optimization in Windows 11, you get TRIM, not defragmentation. In fact, as my computer went through its Optimization process, it said TRIM x% where X rapidly climbed to 100. Thank you for your comment.

@TVeblen Thank you for your comment. I am glad that DISM fixed your issues.

@DigitalGoat Thank you for your comment.

@hsehestedt Thank you for clarifying what TRIM is and how it works. It definitely seems that TRIM is a good thing to do.


I hope others besides myself found this thread helpful. Thank you, everyone!