Avira Update, this was a pill to uninstall! With each failed attempt below, the program would return to Programs and Features, a shortcut on the desktop and an icon in the task bar next to the clock.
Numerous failed attempts to uninstall via:
- Avira standard uninstall procedure (from your first link:) (Did a reboot after each attempt)
- Avira Registry Cleaner
- Revo Uninstaller
- Deleting from the registry
Finally I had success by:
1. Following the manual uninstall (https://www.avira.com/en/support-for-home-knowledgebase-detail/kbid/902)
2. Booting into Windows 10 safe mode (https://www.avira.com/en/support-for-home-knowledgebase-detail/kbid/1778)
3. Renaming Avira in the Program86 folder and Program Data folder.
4. Rebooting into Safe Mode, I was successfully able to delete the folders!
As soon as Avira was successfully uninstalled, Windows Defender turned back on.
Note: The Avira Registry Cleaner would not function in safe mode, but it did so when I returned to Windows 10 normal mode.
Thank you for your assistance!