Microwave interior paint is peeling, rust is visible, or there are rough spots inside the cavity.

Safety: Small rust spots are usually cosmetic but can lead to arcing if metal is exposed.

Cleaning and prep:

• Unplug the microwave.
• Clean the affected area thoroughly and dry it.
• Lightly sand loose paint and rust with fine sandpaper, avoiding deep scratches.

Repair:

• Apply microwave-safe cavity touch-up paint recommended by the manufacturer to cover bare metal.
• Allow paint to cure fully per product instructions before using the microwave.

Severe corrosion: If rust is extensive or structural, replacement of the microwave is often recommended for safety.