Run the oven at about 150 for a while - so that the metalwork can expand slightly - then as soon as you feel confident use a damp cloth to grip the glass cover.
Unscrew Anticlockwise
Good luck...
Peccavi, February 2011
heat it up with a hair dryer,then use a dry cloth to remove or rubber gloves
mm, February 2011
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I can answer this question...
How can I undo a jammed glass cover over oven light bulb?
