I bought 2018 home and business at Office Depot. When I installed and started I didn't get a sign-in prompt. Should I start another way? "

[SanfordS]

If you are using a version of TurboTax that is installed locally on your computer, then you do not need to log in to anything.

[wasson]

I installed it on a different computer than I used last year.  How do I import data?  Or do I need to reinstall on the old computer?

[SanfordS]

You don't need to re-install TurboTax on the old computer.  But you do need to copy the TurboTax file of last year's return from the old computer to the new one.  If you're not sure where it's saved to on the old computer and do a search for it, search for a file that ends in .tax2017

Copy that file to the new computer and when starting a new return on the new computer, select the import option and point it at that .tax2017 file.