Microwave cavity paint is peeling or rust is visible inside, especially on the floor or around the door.

Steps:

• Stop using if metal exposed: If bare metal is exposed and rusting, discontinue use until repaired, as arcing can occur.
• Clean area: Thoroughly clean the cavity with mild detergent and dry completely.
• Light rust repair: For small spots, gently sand away loose rust, clean, and apply a microwave-safe cavity touch-up paint recommended for appliances. Allow to cure fully before use.
• Severe corrosion: If rust is extensive or structural, replacement of the microwave is usually safer than repair.

Warning: Do not use ordinary household paint inside the microwave.