What problems occur if I used Turotax Download in 2017 and now use Turbotax Online in 2018? I got a new computer and the 2017 software was lost.

[turbotaub]

Turbotax Download in 2017; Turbotax Online in 2018. Compatible?

[VolvoGirl]

You will need to have the 2017 data file ending in .tax2017 on your computer.  Did you save that?  Have a backup copy?  You don't need the 2017 program installed.

[DoninGA]

You can import the 2017 tax data file from the TurboTax desktop editions to the 2018 online edition.

See this TurboTax support FAQ for importing 2017 tax data using the online editions - https://ttlc.intuit.com/questions/1900883-how-do-i-transfer-last-year-s-return-into-turbotax-online