(1) A document to be served under this Act by one person ("the server") on another person ("the subject") is to be treated as properly served on the subject if dealt with as mentioned in the following subsections.
(2) The document may be delivered or sent by an appropriate method to the subject, or addressed to him by name and left at his proper address.
(3) For the purposes of this Act, a document sent by post to, or left at, the address last known to the server as the address of a person shall be treated as sent by post to, or left at, his proper address.
(4) Where the document is to be served on the subject as being the person having any interest in land, and it is not practicable after reasonable inquiry to ascertain the subject's name or address, the document may be served by-
(a) addressing it to the subject by the description of the person having that interest in the land (naming it), and
(b) delivering the document to some responsible person on the land or affixing it, or a cop
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