Police, fire and ambulance services attended a flat fire above Boyes in Nottingham Road on Sunday.
Derbyshire fire service confirmed crews from Alfreton and Ripley attended the blaze at around 11am.
They received reports of smoke in the corridor and forced entry into the flat before discovering the fire was already out.
A police spokesperson said: “We were there just as a precaution. When the emergency services arrived it was found that it was a microwave causing the smoke but no one was injured.”