I also ran into this issue as well when I replaced my computer with a new one. I certainly did not install the software on 5 computers, but I still got the message. I tried repairing the software, uninstalling the software, turning off my antivirus and firewall, etc.. without success. Strangely, I noticed that I only get the activation message when launching TurboTax 2019 after I plug my flash drive with my tax file on it. If I launch TurboTax 2019 without my flash drive connected, I do not get the activation message. I then plug in my flash drive and am able to work on my taxes without issue. I have been able to replicate this numerous times, so I have learned to attach my flash drive AFTER starting TurboTax 2019. I hope this works for/helps someone else.
