Instructions from Canada Post:

The following was received by a resident after a complaint to Canada Post about junk mail delivered to the Angus Glen area

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“I have forwarded your comment and request to your local depot to stop
all unaddressed admail delivery into your community mail box.
The delivery of unaddressed admail should stop within 2-5 business
days.

Consumers who do not wish to receive unaddressed material should put a note to this effect on their mail receptacle. The note should be placed inside the receptacle in the case of a community mailbox, group mailbox or postal box.

As a result of such a note being placed on or inside a mail
receptacle at a particular address, Canada Post will no longer
deliver the following mail items: free samples, coupons, flyers and
newspapers, government mailings, free distribution magazines,
catalogues, non-profit and event information. As well, Canada Post
will no longer deliver municipal service notices (e.g. schedule of
snow removal, changes in garbage pick-up, announcement of town hall
meetings). However, since Canada Post is only one of many
distributors of unaddressed materials,consumers may continue to
receive these materials from other
distributors.

The only unaddressed materials that Canada Post will continue to
deliver to these customers are as follows: community newspapers, as
well as House of Commons, provincial chief electoral officers,
municipal
electoral offices and Elections Canada mailings.

Regards,

Yves Douville
Customer Service” Canada Post