80% of error 87 cases are simple typos. Compare your command against the correct syntax:
Correct DISM syntax for checking health:
DISM /Online /Cleanup-Image /CheckHealth
Correct DISM syntax for restoring health:
DISM /Online /Cleanup-Image /RestoreHealth
Common typos that cause error 87:
Pro tip: Use TAB completion in Command Prompt. Type
DISM /Online /Cleanup-Image /then press TAB to cycle through valid options. dism error 87 fixed
Try a basic check first:
DISM /Online /Cleanup-Image /CheckHealth
If that works, the problem is likely in your longer command’s syntax, not DISM itself.
DISM Error 87 ("The parameter is incorrect") commonly occurs when running the Deployment Image Servicing and Management (DISM) tool on Windows. This report explains causes, diagnostics, and a comprehensive set of solutions, including step-by-step commands, troubleshooting flowcharts, and preventive measures. Target audience: system administrators and advanced users troubleshooting Windows image servicing failures on Windows 7 through Windows 11.
DISM /Online /Cleanup-Image /CheckHealth
If your source path has spaces, enclose it in quotes: 80% of error 87 cases are simple typos
/Source:"E:\sources\install.wim:1"
If you copied a command from a website, ensure it doesn’t include placeholder text like <source> or brackets. For example:
Incorrect:
DISM /Online /Cleanup-Image /RestoreHealth /Source:<path> ❌
Correct:
DISM /Online /Cleanup-Image /RestoreHealth /Source:C:\RepairSource\install.wim
If you are using the /RestoreHealth command and pointing to a specific Windows installation media (like a mounted ISO or USB drive) to fix a corrupted system, Error 87 can occur if the path to the "install.wim" file is incorrect or formatted improperly. Correct DISM syntax for restoring health: DISM /Online
The Fix:
Ensure you are pointing to the correct file inside your installation media, usually located in the sources folder.
Correct Syntax:
DISM /Online /Cleanup-Image /RestoreHealth /Source:wim:D:\sources\install.wim:1 /limitaccess
Tip: To find the correct index number, run the following command to list the available versions inside your WIM file:
DISM /Get-WimInfo /WimFile:D:\sources\install.wim