Where can I find my tax forms for 2017, 2016,2015

TurboTax and the IRS save returns for seven years.  After seven years they are gone.   You might still find 2017.

  You have to access your own account and/or  print it for yourself using exactly the same account and user ID that you used when you prepared the return.

 https://myturbotax.intuit.com/

Start a 2024 return online and enter some personal information  so that the menu on the left opens up and lets you access your past year returns.

https://ttlc.intuit.com/community/prior-year-return/help/how-do-i-access-my-prior-year-return/01/27010

https://ttlc.intuit.com/turbotax-support/en-us/help-article/import-export-data-files/save-2021-turbotax-online-return-pdf/L8dHfRkpT_US_en_US?uid=m5y4ch1y

Many people have multiple TT accounts and forget how to access them.  Log out of the account you are in now.

https://ttlc.intuit.com/turbotax-support/en-us/help-article/account-management/many-intuit-accounts-turbotax/L9aVfKS1Z_US_en_US?uid=ll5g6zcx

Account Recovery

Or did you use the desktop version of TurboTax?  If so, the files are on your own hard drive or any backup device you used like a flash drive.

https://ttlc.intuit.com/turbotax-support/en-us/help-article/tax-return/find-last-year-tax-data-file-tax-file-computer/L0XJvPaJr_US_en_US?uid=m6gufxei

https://ttlc.intuit.com/turbotax-support/en-us/help-article/data-systems/find-tax-data-file-mac/L4VNGm33S_US_en_US?uid=m6guhab0

You can get a free transcript from the IRS or for a fee of $30, an actual copy of your tax return.

https://www.irs.gov/individuals/get-transcript

https://www.irs.gov/pub/irs-pdf/f4506.pdf

SAVE YOUR TAX RETURNS !

EVERY year before mid-October you should save a copy of your tax return as a pdf and print a copy of it for your records.  That way you will not be searching online frantically when you need it for a lender, FAFSA forms, your next tax return, etc. 

https://ttlc.intuit.com/turbotax-support/en-us/help-article/import-export-data-files/save-2021-turbotax-online-return-pdf/L8dHfRkpT_US_en_US?uid=m6guj526

https://ttlc.intuit.com/turbotax-support/en-us/help-article/import-export-data-files/save-2021-turbotax-online-return-pdf/L8dHfRkpT_US_en_US?uid=m78eb8pc

In order to transfer a past year return to the new return you need the tax file

https://ttlc.intuit.com/turbotax-support/en-us/help-article/import-export-data-files/save-turbotax-online-return-tax-data-file/L4xwOG3LF_US_en_US?uid=m6guk3xl

NOTE:  TurboTax and the IRS save returns for seven years.  Returns older than seven years are purged.