I also found myself in the “NOT ACTIVATING” circle on Windows 11, just like user3153, always only the “buy” option (a one-time offer - we appreciate your loyalty), which has no other option than “BUY” or closing with a cross, uninstalling in safe mode, deleting all (even hidden) Avast folders in the system did not help. After a clean installation from the online installer “online_installation_file_aplikace_avast_free_antivirus.exe”, I again found myself in the circle of being unable to activate avast free. I think Avast “corrupted” the new Avast free installer.
I uninstalled again via safe mode using the “avast_av_clear.exe” utility and in normal mode I deleted all (even hidden) Avast remnants. And finally I installed the offline installation. AND HURRAY, Avast FREE was activated. This procedure (including links) was suggested by the leader “DavidR” under the question “rocksteady” in the thread “Unable to reactivate Avast Free antivirus”. THANK YOU DavidR, thank you very much!! ! !
Clean Reinstall
1 : Download the avast! Uninstall Utility, avastclear.exe Avast Removal Tool | Download Avast Clear | Avast and save it to your HDD. Make a note of the steps required or print the page.
2 : Download the latest Avast off-line installation file for your Avast Program https://files.avast.com/iavs9x/avast_free_antivirus_setup_offline.exe and save to your HDD.
Follow the instructions in the link in 1.