I have a similar problem to that posed by Derek in 2010. The mixer has not been used for 2 years and now won't start, it just make a quiet humming noise. However, I can't turn the drum by hand as Derek could.
Gummed up bearings I suspect - you do not say what problem Derek had 3 years ago - the humming suggests the motor is trying to turn - the lack of movement suggests something is preventing it - your question is in the circular saw category - Ah! it's not a food mixer it's a cement mixer - seized gearbox then.
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