Microwave interior paint is peeling or rust is visible inside the cavity.

Safety note: Small rust spots are common in older units but should be addressed to prevent arcing.

• Clean thoroughly: Remove all loose paint and rust with a non-metallic scrub pad. Wipe clean and dry.
• Sand lightly: Use fine sandpaper to smooth rough edges around chipped areas.
• Apply microwave-safe paint: Use high-temperature, microwave-safe cavity touch-up paint to cover bare metal. Follow the manufacturer's curing instructions.
• Monitor for arcing: After repair, test with a cup of water and watch for any sparks. If arcing occurs, discontinue use and consider replacing the microwave.