Microwave will not start; display works, but pressing START does nothing or beeps and shows E01.

Safety first: Unplug the microwave from the mains. Microwaves contain high-voltage components that can retain a charge even when unplugged. Do not touch the high-voltage capacitor or magnetron area. If you are not experienced with microwave repair, contact a qualified technician.

Basic checks (no cabinet removal):

• Open and close the door firmly several times. Listen for distinct clicks from the door switches.
• Inspect the door latch hooks on the door for cracks, bending, or looseness.
• Check that the door is not sagging: gently lift the door upward; excessive play can prevent switches from engaging.

Further checks (cabinet removal – technician level):

• Remove the outer cover (after unplugging) to access the door interlock switches on the right-hand side of the cavity.
• Visually inspect the primary and secondary door switches for heat damage, broken actuators, or loose terminals.
• Use a multimeter in continuity mode to test each switch: with the door closed, the normally closed (NC) and common (COM) terminals should show continuity; with the door open, continuity should move to the normally open (NO) terminal where applicable.
• Replace any switch that does not change state correctly or shows intermittent readings.
• Inspect and, if necessary, replace the plastic switch mounting bracket if it is warped or cracked, as this can misalign the switches.

When to stop: If you are unsure about working near high-voltage components or cannot access the switches safely, stop and call a Hoover-authorized service technician.