It appears scammers claiming to be from the Canada Revenue Agency (CRA) have added emailing as a way to trap unsuspecting victims.  

Police in Southern Manitoba say they have recently been hearing of scammers sending out emails reporting to be from the CRA telling people a tax refund is in store for them.
    
The email also contains a link to assist the recipient in submitting the refund request.  Police say clicking the link within the email could lead people to provide personal information or allow the scammers to access their computer, or worse.  It could also lock up your computer and lead you to pay a ransom in order to decrypt and free up your hard drive.
    
Aside from the fact that the CRA does not conduct business in this manner, other clues as to its false origin include, poor grammar, incorrect spelling, and of course no reference to the recipient individually, except that it’s sent to your email address.