Chkdsk:
This is a Windows command that can help fix disk errors. From the Microsoft Technet site comes this explanation:
"You should periodically use the Check Disk tool to check the integrity of disks. Check Disk examines disks and can correct many types of common errors on FAT16, FAT32, and NTFS drives. One of the ways Check Disk locates errors is by comparing the volume bitmap with the disk sectors assigned to files in the file system. Check Disk can’t repair corrupted data within files that appear to be structurally intact, however. You can run Check Disk from the command line or through a graphical interface.
You can run Check Disk from an elevated command prompt (Administrator) or within other tools (eg Powershell). At the elevated command prompt, you can test the integrity of drive C by typing the following command:
chkdsk C: (replace C with the drive letter of any other disk you would like to check)
Check Disk then performs an analysis of the disk and returns a status message regarding any problems it encounters.Unless you specify further options, Check Disk won’t repair problems, however.To find and repair errors on drive C, use this command:
chkdsk /f C: (again replace C with any drive letter you want to check)
When you use this command, Check Disk performs an analysis of the disk and then repairs any errors it finds, provided that the disk isn’t in use. If the disk is in use, Check Disk displays a prompt that asks whether you want to schedule the disk to be checked the next time you restart the system. Click Yes to schedule this check. "
If using a rotational drive (Don’t use /r on SSDs) you can also use this command which locates bad sectors and recovers readable information (implies /F) :
chkdsk /r C: (again replace C with any drive letter you want to check and again DO NOT USE on SSDs)
How to get an Elevated Command Prompt:
(From the Lifewire site https://www.lifewire.com/how-to-open-an-elevated-command-prompt-2618088)
How to Open an Elevated Command Prompt in Windows 7 or Vista:
Locate the Command Prompt shortcut, usually in the Accessories folder in the Start Menu.
(Or in Win 7 and Vista it's faster to enter "command" or "cmd" (without the quotes) in the search box at the bottom of the Start Menu and then right click Command Prompt when it appears in the results.)
Once you find it, right-click on it to bring up its pop-up menu of options.
From the pop-up menu, choose Run as administrator. Accept any User Account Control messages or warnings.
An elevated Command Prompt window should appear, allowing access to commands that require administrative level privileges.
How to Open an Elevated Command Prompt in Windows 8/8.1 or 10:
Open Task Manager. The quickest way, assuming you're using a keyboard, is via CTRL+SHIFT+ESC
Once Task Manager is open, tap or click the File menu option, followed by Run new task.
If you don't see the File menu you may first have to click or tap on the More details arrow at the bottom of the Task Manager window to show a more advanced view of the program, including the File menu.
In the Create New Task window you see now, type the following in the Open text field:
cmd
Check the Create this task with administrative privileges box.
If you don't see this box that lilkely means that your Windows account is a standard account, not an administrator account. Your account must have administrator privileges to be able to open an elevated Command Prompt this way.
Now click or press on OK. Follow any User Account Control requirements that might appear next.
An elevated Command Prompt window will appear.
Close Task Manager. It is not needed to remain open to use Command Prompt.
In Win 10 if you Right Click the Start Menu it will have either a listing of either Command Prompt or Powershell (both a regular and Administrator choice). Left click the Administrator choice.
Another way to get an Elevated Powershell Box in Win 10 (if not on the right click Start Menu choice):
To open an elevated PowerShell prompt, in the taskbar/Cortana search, type powershell.
Now find the result Windows PowerShell which appears on the top.
Right-click on it and select Run as Administrator.
The UAC prompt will ask you for your consent. Click yes, and the prompt will open.
An elevated PowerShell prompt will display Administrator: Windows PowerShell on the top in the prompt’s border.
