1-Netfile is only available for the previous 5 years, which are 2017 to 2022, through the Canada Revenue Agency (CRA) therefore, 2017 and older will have to be sent in by mail.
Please see this Canada Revenue Agency link: File your taxes online: Understand NETFILE.
2-You can use TurboTax software starting in 2016 File past years' taxes but you will need to get a older paper returns from the Canada Revenue Agency (CRA) Tax packages for all years.
Mailing address for CRA
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