What causes fix dism error 87 — the parameter is incorrect on Windows?

Common causes of fix dism error 87 — the parameter is incorrect include: Incorrect DISM command syntax — wrong spacing or missing slashes, Running DISM from a non-elevated Command Prompt, Corrupted Windows component store preventing DISM operation, DISM version mismatch — using an older DISM with newer Windows image, Invalid or inaccessible source files specified in the command, System drive file system corruption affecting DISM operations.

How do I know if I have fix dism error 87 — the parameter is incorrect issues?

Common symptoms of fix dism error 87 — the parameter is incorrect include: DISM /Online /Cleanup-Image /RestoreHealth returns "Error: 87", "The parameter is incorrect" when running any DISM command, DISM /ScanHealth completes but /RestoreHealth fails with error 87, DISM commands work for some operations but fail for others, Error occurs immediately after entering the DISM command, DISM error 87 appears during Windows repair or feature installation.

Fix Fix DISM Error 87: The Parameter Is Incorrect

Symptoms

You might be experiencing this problem if you notice:

•DISM /Online /Cleanup-Image /RestoreHealth returns "Error: 87"
•"The parameter is incorrect" when running any DISM command
•DISM /ScanHealth completes but /RestoreHealth fails with error 87
•DISM commands work for some operations but fail for others
•Error occurs immediately after entering the DISM command
•DISM error 87 appears during Windows repair or feature installation

Common Causes

⚠Incorrect DISM command syntax — wrong spacing or missing slashes
⚠Running DISM from a non-elevated Command Prompt
⚠Corrupted Windows component store preventing DISM operation
⚠DISM version mismatch — using an older DISM with newer Windows image
⚠Invalid or inaccessible source files specified in the command
⚠System drive file system corruption affecting DISM operations

Solutions

Solution 1: Verify Correct DISM Syntax

1The most common cause is incorrect syntax — verify carefully:
2Open Command Prompt as Administrator (this is required)
3Correct syntax: DISM /Online /Cleanup-Image /RestoreHealth
4Note: there must be a space before each forward slash
5Wrong: DISM/Online (no space) — this causes error 87
6Wrong: DISM /Online /Cleanup-Image/RestoreHealth (missing space)
7Copy and paste the exact command to avoid typos
8Also verify: DISM /Online /Cleanup-Image /ScanHealth (runs a scan first)

Solution 2: Run DISM with Alternative Source

1If syntax is correct but still fails:
2Try specifying a Windows source image:
3Mount Windows 10/11 ISO (right-click → Mount)
4DISM /Online /Cleanup-Image /RestoreHealth /Source:D:\Sources\install.wim
5Replace D: with your mounted ISO drive letter
6Add /LimitAccess to prevent Windows Update fallback:
7DISM /Online /Cleanup-Image /RestoreHealth /Source:D:\Sources\install.wim /LimitAccess
8If using install.esd instead of .wim, the syntax is the same

Solution 3: Fix Underlying Corruption

1If DISM itself is broken:
2First try: sfc /scannow (this doesn't depend on DISM)
3If SFC finds errors it can't fix, try DISM from Safe Mode:
4Boot into Safe Mode with Command Prompt
5Run: DISM /Online /Cleanup-Image /RestoreHealth
6If still failing, try the Windows Update standalone method:
7DISM /Online /Cleanup-Image /RestoreHealth /Source:wim:D:\Sources\install.wim:1
8The :1 specifies the image index (usually 1 for single-edition ISOs)
9As a last resort: perform an in-place Windows repair upgrade

FIXES THIS IN 5 MINUTES