Firewall - wie kann ich andere Virenschutzprogramme blockieren?

wie kann ich AVIRA blockieren?

Hello ‘Benutzer274’ welcome to the Avast Community Forum

This is the the Avast Community Forum, do you actually have the Avast One Antivirus program installed ?
If so, it isn’t advised to have two active antivirus programs installed as they are likely to conflict/clash.

You should uninstall Avira to remove the conflict.

Sure, I know. But uninstall is not possible, not successfull. It should be possible to use the Avast-firewall rules to block Avira-requests…

No - Avast doesn’t block as such, it is an Antivirus program - the problem is conflict.

Why can’t Avira be uninstalled, e.g. what errors are you getting ?

This is just one hit from a google search on what you are asking.
How to uninstall AVIRA - https://support.avira.com/hc/en-us/articles/360003162153-Uninstallation-of-Avira-for-Windows