These links have several trouble shooting tips:
https://ttlc.intuit.com/questions/1900386-error-the-selected-file-is-not-a-previous-year-tax-file-or...
https://ttlc.intuit.com/questions/4197873-i-tried-uploading-a-tax2016-file-from-the-desktop-version-...
https://ttlc.intuit.com/questions/1900269-troubleshoot-transferring-from-a-prior-year-return
Would you please let me know if you've tried them and if you're still having an issue?
