Apologies if this topic has already been discussed. A person I heard of recently thinks that by the priest saying "all" instead of "many" at the consecration makes the mass invalid. They refuse to receive communion because of this.
My understanding is proper translation was reverted to "many" by Pope Benedict. So priest is not using approved language. Maybe rather than not taking the Eucharist, this person should speak to priest about it? But having said this , even with this mistake, as long as he says "this is my body" and "this is my blood", I believe Eucharist and Mass is valid. But , still I would speak to the priest.