Confirm the top of your command window says "Administrator". Ensure the Windows Update service status is "Running". To help narrow down the solution, tell me:
Error: 87 – The option is unknown. For more information, refer to the help by running DISM.exe /?.
DISM /Online /Cleanup-Image /RestoreHealth /Source:E:\sources\install.wim dism error 87 fixed
| Practice | Why it helps | | :--- | :--- | | | This is the #1 cause of the error. | | Copy-paste from trusted sources | Eliminates typographical errors. | | Use Tab completion | Type DISM /On then press Tab to auto-fill correctly. | | Run as Administrator | Non-admin CMD cannot execute DISM properly. | | Check for trailing spaces | A space after a colon can also cause errors. |
If the DISM utility binaries themselves are corrupted, the tool cannot execute parameters correctly. Running the System File Checker (SFC) scan can patch the local executable files. Open . Type the following command and hit Enter: sfc /scannow Use code with caution. Confirm the top of your command window says "Administrator"
If you consistently get Error 87 in CMD, try the equivalent. The syntax is slightly different but often more forgiving.
: Using a DISM command that your specific version of Windows does not support. For more information, refer to the help by running DISM
He reset his approach. The command structure for an offline repair required pointing to the source WIM file.
While seeing "The parameter is incorrect" can be alarming, DISM Error 87 is usually a simple matter of formatting permissions
Users most commonly encounter Error 87 when running: