[SOLVED] What is the write size of a sfc /scan and can doing a scan ever mess up system files/permissions at any time?

ShangWang

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Mar 26, 2021
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Does anyone know about how many gigabytes a sfc scan does?

Does the size equal the system file size of ALL windows installation files, and if so how big/what portion is it?

Will it only scan the OS drive?
 
Solution
You shouldn't need to SFC /scannow at all unless you are having problems. Its not something I do unless I think of it, or I am bored.
it doesn't touch permissions
it fixes System files, its not going to break any.

ShangWang

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Mar 26, 2021
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I just ran it on my Win 11 system.
Fixed a few things.
It resulted in a log file of 7.45MB.
I see, the log file itself is 7.45MB or the amount of writes written is that amount? I heard doing the scan a lot is just generally not good because it causes a lot of writes on a SSD, I would assume it's in the GB size.
 

USAFRet

Titan
Moderator
I see, the log file itself is 7.45MB or the amount of writes written is that amount? I heard doing the scan a lot is just generally not good because it causes a lot of writes on a SSD, I would assume it's in the GB size.
Well, there is no reason to "scan" all the time.

And I believe, it is only a read, unless it need to fix something. That would be a write.

But if it needs to be fixed, any write cycles incurred to the SSD is irrelevant, because it presumably needs to be fixed.

Lastly, paople are FAR too worried about write cycles on their SSDs.
 

ShangWang

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Mar 26, 2021
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Well, there is no reason to "scan" all the time.

And I believe, it is only a read, unless it need to fix something. That would be a write.

But if it needs to be fixed, any write cycles incurred to the SSD is irrelevant, because it presumably needs to be fixed.

Lastly, paople are FAR too worried about write cycles on their SSDs.
I agree, though I know it's unnecessary to do these write tasks so often on a drive in general, I'm just curious about the size which I assume is not very big if it only causes writes if fixes need to be done.

I just thought it was a lot since sfc /verifyonly exists, I had it in one of my list of commands I could use and assumed it was there because it helped prevent unnecessary writes since it only read.
 

USAFRet

Titan
Moderator
I agree, though I know it's unnecessary to do these write tasks so often on a drive in general, I'm just curious about the size which I assume is not very big if it only causes writes if fixes need to be done.

I just thought it was a lot since sfc /verifyonly exists, I had it in one of my list of commands I could use and assumed it was there because it helped prevent unnecessary writes since it only read.
/verifyonly does not exist because of a lot of write cycles to an SSD.
It may just be for a time consideration, or to see what, if anything, needs to be fixed.
 

Colif

Win 11 Master
Moderator
You shouldn't need to SFC /scannow at all unless you are having problems. Its not something I do unless I think of it, or I am bored.
it doesn't touch permissions
it fixes System files, its not going to break any.
 
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