I have the SAME LICENSE ACTIVATION ERROR trying to open up my 2021 tax file as others have reported.
My sin? installing an additional SSD to my computer recently!
Yes, you got that right. adding an additional hard drive makes TurboTax thinks that I am running the copy on a new computer. What a genius algorithm!
I had to go through all the trouble of backing things up so I can physically remove the installed SSD drive.
TurboTax 2021 started up successfully as soon as the drive is removed!
Very disappointed with Intuit but hey, at least I am able to open and read my last year's tax. :(
