It's very cold outside and my power windows won't work. Is it the cold?

There is a good chance that moisture has gotten to the parts that allow the glass to side. This moisture may have frozen so yes it is quite common that windows may not function in cold weather. Don't force it either because the window regulators on these are mostly made of plastic bits and they will break. Hope your windows worked after it warmed up. Kind Regards, Stephane BMW Excluservice www.bmwexcluservice.com