If CRA (the Canadian Income Tax Department) has challenged any Canadian income tax returns that you have filed, be sure that you keep all original documents related to the year being challenged until the matter is finally settled.
"This article provides information of a general nature only. It is only current at the posting date. It is not updated and it may no longer be current. It does not provide legal advice nor can it or should it be relied upon. All tax situations are specific to their facts and will differ from the situations in the articles. If you have specific legal questions you should consult a lawyer."