If you're transferring last year's PDF into the 2020 TurboTax for Windows CD/Download software, in some cases TurboTax won't be able to read the PDF, for example if it's password-protected or is a scanned copy of a PDF instead of an actual PDF file. 

Instructions

1. Open your TurboTax 2020 program and choose New Tax Return from the File menu in the upper left corner.
2. Click Start a New Return.
3. When you get to the transfer screen, click Browse.
4. Navigate to your PDF file, click Open, and follow any onscreen instructions.

Related Information:

• What's the difference between the tax data file and the PDF file?
• Transfer last year's return to 2020 TurboTax for Windows
• Error 102346

Turbotax does not accept the name on my 1040 for last year.  I may not use turbotax if it will not accept last years returns.

Are you using the Online version or the Desktop program?  What did you use last year?  You really should use the Turbo Tax data file ending in .tax2019 to transfer or for online be logged into the same account.  If you are transferring from online to Desktop I can tell you a couple different ways to do it.

How to transfer into the Online version

https://ttlc.intuit.com/community/entering-importing/help/how-do-i-transfer-last-year-s-return-into-...

How to transfer into Windows Desktop

https://ttlc.intuit.com/community/entering-importing/help/transfer-last-year-s-return-to-turbotax-fo...

How to transfer into Mac Desktop

https://ttlc.intuit.com/community/tax-data-file/help/how-do-i-transfer-last-year-s-return-into-the-t...