Chkdsk (check disk) is a system utility that’s built into the Windows operating system. You can use it to check for and repair problems with your hard drive and the file system.
How To Use Chkdsk.
The check disk utility is generally run from the command prompt (although it works exactly the same in PowerShell & Windows Terminal).
Left click on the Start button and then type “cmd”. Right click on Command Prompt (app). Then left click “Run As Administrator”.
You’ll need to click Yes on the UAC pop up that appears.
Enter The Chkdsk Command Into Command Prompt..
When the Command Prompt window opens you need to type in the chkdsk command along with the drive letter of the hard drive that you want to test. Then you’ll need to add what’s called a “switch”.
The switch (also called an option, a parameter or sometimes a flag) tells check disk what it should do. While there are many switches that you could use, the two most useful for home computer users are the /f switch and the /r switch.
Enter the check disk command like this
chkdsk c: /f
Or to use the /r switch, enter it like this
chkdsk c: /r
and then press the Enter key on your keyboard.
What The /f & /r Switches Do?
The /r switch checks both the file system and the physical surface of the drive and can run for several hours depending on your computer.
When you’re running a disk check, it’s obviously better to us the /r switch if you can. That’ll check and attempt to repair the whole drive, but it really could run all night.
Cannot Lock Current Drive Message.
After pressing the Enter key you’ll probably see this message appear in the Command Prompt window.
“Chkdsk cannot run because the volume is in use by another process. Would you like to schedule this volume to be checked the next time the system restarts? (Y/N)“
What it means is that chkdsk requires exclusive access to the drive. It cannot operate properly if you (the user) or any programs try to access the files stored on the drive.
To continue, type the letter “Y” and then press the Enter key.
Using Chkdsk On Your System Drive.
The system drive is the hard drive that contains your Windows installation. Usually it’ll be labelled as the C: drive in File Explorer. Chkdsk can’t check your system drive while it’s in use, so you’ll need to restart your computer.
- Close the Command Prompt window using the X in the top right corner and then restart your computer.
- As your computer restarts, you’ll see a prompt to skip the disk check by pressing any key. Don’t press any key on your keyboard.
- If you don’t hit a key then chkdsk will begin scanning and repairing your hard drive and file system.
Checking A Storage Drive (Non System Drive).
Chkdsk can check any drive on your computer, not just the system drive. If you need to check other drives within your PC, simply change the drive letter in the command.
For example, on this computer I have a second hard drive, Backup Drive (e:).
To check the file system of the Backup Drive with the /f switch, I’d type
chkdsk e: /f
Or to check the entire drive, change the switch to /r
chkdsk e: /r
After locking the drive, the disk will be checked. Since it’s not the system drive, it can be checked while your still using your computer.
Your Drive Will Be Unavailable During A Disk Check.
Since chkdsk locked the drive, you won’t be able to access any of the files, folders and any other data on the drive.
How To Use Chkdsk.
- Launch Command Prompt as Administrator
- Type chkdsk space your drive letter space then add the switch you want to use, either /f or /r
- For a C drive it would look like this chkdsk c: /r
- Press Enter on your keyboard.
- If you’re checking your system drive, you’ll need to press the letter Y and then re-start your computer.
When To Use Chkdsk?
Run chkdsk periodically. Depending on how much use the computer gets, running a disk check 2 to 4 times a year should help to keep both your hard drive and file system in tip top shape.
Ideally you should also run a disk check after what is often called “an unexpected shutdown”. In other words a system crash. Any time your PC suddenly goes off (maybe because it crashed or suddenly lost power), that can cause corruption in the Windows file system. It can also cause physical damage to your hard drive, resulting in bad sectors (unreadable areas of the disk).
Check Disk Can’t Repair A Failing Drive.
If your hard drive is beginning to fail, then replace it as soon as you possibly can. Neither chkdsk nor any other hard drive utility can save or repair failing drives.
Backup your data immediately and then get the drive replaced.
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