In case you are using a Samsung Microwave, Error 21 or E21 is Thermistor Short error. It is caused when the thermistor sensor, which senses the temperature of the cavity inside does not work properly.
To correct this, unplug the power cord and wait for more than 10 seconds. Plug the power cord again. If the symptom persists, contact the nearest service centre
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In case you are using a Samsung Microwave, Error 21 or E21 is Thermistor Short error. It is caused when the thermistor sensor, which senses the temperature of the cavity inside does not work properly.
To correct this, unplug the power cord and wait for more than 10 seconds. Plug the power cord
again. If the symptom persists, contact the nearest service centre