In one place you say *.tax2024, then you go on to say *.ta24, so that's kind of confusing and needs clarification. You can only transfer a *.tax2024 data file into Online TurboTax. How was your 2024 return prepared? Was 2024 prepared in desktop TurboTax software, and are you trying to transfer a *.tax2024 data file from your computer into Online TurboTax?
I see you have another thread here:
https://ttlc.intuit.com/community/taxes/discussion/the-selected-file-is-not-a-previous-year-tax-file...
"stuck on personal info when i logged back in"
If using Online TurboTax try the transfer again, which will clear your return. Be sure the *.tax2024 data file is not password-protected (Windows) or encrypted (Mac).
Log in and open your Online return.
Select the tab Tax Tools from the left-column menu, and then Tools.
In the Tools window, select Transfer last year's TurboTax return from your computer and follow the prompts.
