Products:
Avira Antivirus Pro 2018/2019 [macOS]
Avira Free Antivirus 2018/2019 [macOS]

Operating systems:
Apple macOS 10.14.x (Mojave)
Apple macOS 10.13.x (High Sierra)
Apple macOS 10.12.x (Sierra)
Apple Mac OS X 10.11.x (El Capitan)
Apple Mac OS X 10.10.x (Yosemite)

Problem:
After using an Uninstall Tool providing by Avira removes Avira Free Antivirus, the traces of the Avira Free Antivirus installation are not entirely deleted.

Cause:
The Avira Uninstall Tool cannot recognize all the installed files/folders associated with Avira Free Antivirus.

Leftover files/folders:

Avira in /Library/Application Support/Avira
com.avira.connect-installer in ~/Library/Caches/
com.avira.Iris in ~/Library/Containers
com.avira.stats.service in ~/Library/Containers
com.avira.connect-installer.log in ~/Library/Logs
com.avira.controlcenter.savedState in ~/Library/Saved Application State

Uninstall Steps:
Completely and automatically remove Avira Free Antivirus and all its leftover files/folders. If you want to clean out all leftover files/folders, you can use Mac X Uninstaller.

Note: Before removing Avira Free Antivirus, We suggest you watch the video below first.

Step 1. Download Mac X Uninstaller and install it. Download Link here: https://macxuninstaller.com/download

Step 2. Start Mac X Uninstaller and click the icon of Avira Free Antivirus in the list view on the home screen of Mac X Uninstaller.

Step 3. Click on ‘Run Analysis’. Wait a few seconds, the files/folders of Avira Free Antivirus are listed.

Note: After the completion of ‘Run Analysis’, you must not click on ‘Complete Uninstall’ but should perform the following Step 4.

Step 4. Open the /Applications folder, find the icon of Avira Free Antivirus, and click it.

Step 5. Click Avira’s drop-down menu on the top-left of the macOS desktop and select ‘Help’ -> ‘Open Uninstaller’.

Step 6. After the Avira Antivirus Uninstaller appears, please follow the uninstallation instructions and perform.

Step 7. Go back to Mac X Uninstaller and click on ‘Complete Uninstall’. The Mac X Uninstaller will automatically remove Avira Free Antivirus and all its leftover files/folders.

Step 8. reboot your macOS.