I've used Turbo Tax for many years, yet I'm being told I'm a new customer; therefore, can't download a copy of my 2016 tax returns.

[ErinH · Accepted solution]

It sounds like you may have multiple accounts. Many users accidentally create multiple UserID's that are associated with the same email. Please see this FAQ to troubleshoot. When you select the blue go here it will take you to the account recovery page which will show you all the accounts associated with your informatiom: https://ttlc.intuit.com/replies/3290682