Microwave will not start; display shows E01 shortly after pressing Start.

Safety first: Unplug the microwave from the wall outlet before any inspection. High-voltage components inside a microwave can retain a dangerous charge even when unplugged. Do not remove the outer cabinet unless you are trained; limit checks to the door and accessible areas.

• Check door closure: Open and close the door firmly. Ensure nothing is obstructing the door (warped trim, foil, food debris). The door should close evenly and latch with a solid click.
• Inspect door latches: With power disconnected, examine the plastic latch hooks on the door. If they are cracked, loose, or not springing back, the interlock switches may not be actuated correctly. Replace the door latch assembly if damaged.
• Check for door play: Gently lift the door up and down. Excessive play can prevent the interlock switches from engaging. Tighten hinge screws if accessible from the front (do not remove the cabinet).
• Reset power: After checking the door, plug the microwave back in and try again. If E01 persists, the primary or secondary door switch or wiring is likely faulty and should be tested and replaced by a qualified technician.

When to stop: If the error remains after basic door checks, do not bypass or tape switches; this is a critical safety system. Contact a Bosch-authorized service center.