DISM /Online /Cleanup-Image /RestoreHealth
By carefully reviewing your command, ensuring /Online: has the colon, and running the tool with administrative privileges, you will resolve this error in under two minutes. For the rare cases where the error persists, repairing your system files with SFC or switching to PowerShell will get the job done. dism error 87 fixed
Missing colon after Online .
If you are copying commands from a website, paste them into Notepad first and look for auto‑formatted slashes. If you are unsure about a specific DISM switch, let DISM teach you the correct format. If you are copying commands from a website,
Typically displayed in the Command Prompt as Error: 87 – The option is unknown , this error halts your repair efforts immediately. While the message sounds vague, it is actually a very specific syntax error. The good news? It is almost always fixable within minutes. While the message sounds vague, it is actually
DISM /Online: /? DISM /Image: /? DISM /Cleanup-Image /? If a particular switch doesn’t appear in the help list, it doesn’t exist in your version of Windows (e.g., some switches are only for Windows PE). If your path contains spaces or unusual characters, wrap the path in double quotes and escape spaces properly.