Dism Error — 87 Fixed

Find , right-click it, and select Properties .

) is the primary trigger. Beyond typos, the error occurs if: How To Fix DISM Error 87 (Cleanup-Image Option is Unknown) dism error 87 fixed

The most frequent cause is missing spaces before the forward slashes ( / ). Windows Command Prompt is very strict about this. ❌ DISM/Online/Cleanup-Image/RestoreHealth ✅ Correct: DISM /Online /Cleanup-Image /RestoreHealth Find , right-click it, and select Properties