This subject came up in a very long thread but I thought it deserved its own thread so that everyone who spends their monies to send any correspondence CMRRR gets positive proof. Always, always put into the letter the # that matches the number on your green card. Scummie CA P.O. Box 12345 Too many places, USA state Re: Acct # Sent Certified Mail Return Receipt XXXXXXXXXX This will then absolutely prove the CA, CRA or OC received that exact letter. Therefore if you ever have to sue there will be no way they can deny ever receiving the letter. The green card has less teeth unless you can PROVE that that letter was indeed in the envelope sent CMRRR. HTH, clc