How to safely stop a `chkdsk /r /f C:` on Windows 10?

Question

I started a chkdsk /r /f C: on Windows 10, but now that it's running I want to cancel it. Just powering down the computer risks corruption, so how can I safely abort it?

Ctrl+C isn't an option: I'm running chkdsk /r /f on the drive that has Windows installed. This cannot be done while Windows is running, but only during startup (outside of CMD). This doesn't respond to ctrl+c.

Note: the linked duplicate question is NOT the same. That question is about running chkdsk without parameters, and that is safe because it runs in read-only mode. The /r /f flags causes chkdsk to run in read-write mode, so then it's not generally safe to just kill the process. It needs to be terminated gracefully. Some implementations of fsck (linux equivalent) can be stopped gracefully - even in repair mode - so theoretically it should definitely be possible to safely stop a chkdsk procedure. The main question is: did the Windows devs actually implement a graceful cancellation procedure, and if so how do I trigger it?

Answer 1

You can't stop chkdsk process once it started. The safe way is to wait until it completes. Stopping the computer during the check might lead to filesystem corruption.

Answer 2

Edit: As noted in the comments, there is no safe option (but you could use more or less riskier moments).

If it is running in the pre-startup and you are past Stage 3, meaning it is on 4 of 5 or 5 of 5, then you can just restart your machine. I have done it on stage 5 of 5, which is the stage of checking the free space, and it started up just fine. If you restart your machine during stages 1 to 3, you run the risk of losing data.

Source: Norman Picard

Answer 3

Don't know if safe, but I successfully stopped CHKDSK with the following line command on an elevated cmd window:
taskkill /F PID nnnn
Where nnnn is the Process ID for the running CHKDSK.
To obtain the PID, open the Task Manager and look at CHKDSK -> right click - Go to details
To run an elevated cmd window, go to taskbar, search -> cmd (or command prompt) - right click - Run as administrator.
I did it in the first stage, when searching for errors, so i hope it was pretty safe.
In a stage where it is writing fixes could be risky i think.
My unit already reported unspecified "errors" before this in a previous read-only run, so I started with /F fix option, but then I decided to stop to try better techniques.

Answer 4

Here's my output from chkdsk

File record segment 36383 is unreadable.
 1 percent complete. (36384 of 247328 file records processed)
File record segment 36384 is unreadable.
 1 percent complete. (36385 of 247328 file records processed)
File record segment 36385 is unreadable.
 1 percent complete. (36386 of 247328 file records processed)
File record segment 36386 is unreadable.
 1 percent complete. (36387 of 247328 file records processed)
File record segment 36387 is unreadable.
 1 percent complete. (36388 of 247328 file records processed)
File record segment 36388 is unreadable.
 1 percent complete. (36389 of 247328 file records processed)
File record segment 36389 is unreadable.
 1 percent complete. (36390 of 247328 file records processed)

I think it's safe to kill the PID in my case ;)

Answer 5

I got really impatient, since it was counting like 300k from 2000k+ (I don't know what was it counting, I don't know about OS), and hit Alt+F4 in the cmd window. I believe this is smoother than killing it from the task manager.

Answer 6

Alt/F4 was my exit. Immediately did a W10 disk scan. No errors found. Glary Utilities has a disk check feature. It will let you stop any check. Did a file check with that and then a scan for bad sectors. All seems well at this point.