How to open a bottle when the stopper will not move:
The idea is to get the neck of the bottle warmer (which will make the glass expand) while keeping the stopper colder. There are many suggestions and usually the best is to wrap something hot (from HOT water faucet) around the neck, and gently move the stopper back and forth.
One way to get it out is to brace the bottle or have a buddy hold it. Throw two or three loops of cotton string around the neck of the bottle (a shoe lace works well). Holding the ends of the string tight, with a sawing motion, pull the string back and forth. After about 3 to 4 minutes of this, the friction of the string will have heated the neck of the bottle, causing it to expand and release the (colder) stopper. Before you put the stopper back into the bottle, grease it lightly with stopper grease or petroleum jelly. Don't put a cold stopper into a hot bottle.
DO NOT USE ANY OTHER METHOD to heat the neck of the bottle. The heat of an open flame, for instance, cannot be controlled and it may cause the bottle to explode or crack.
A (quicker) variation is to wet a cloth with water from the hot tap (about as hot as you can stand when you wring it out - but no hotter), and wrap it round the neck of the bottle or decanter.
Problems like this occasionally occur due to shipping conditions (cold if by plane, hot if by boat). To prevent this in the future (once you get it open) rub a little vaseline on the stopper .
