Enhanced Firewall cannot be activated in 21.3.2459

[Goldfisch]

Since yesterday upgrade to 21.3.2459 the enhanced Fire Wall of APS is not active any more.
Warning "You are not protected" appears.
It is not possible to activate the FW manually.
If I run a Smart Scan, the problem is identified and seems to repair (they say: you are now protected by the enhanced FW), but afterwards the FW is still deactivated.
I tried to repair the installation (deinstallation and re-installation), but no result.
I am running it on Windows 7 Professional. Window's own Fire Wall is active.
What can I do? Can you fix it for me.

[Asyn]

- OS..? (32/64 Bit..? - which SP/Build..?)
- Other security related software installed..?
- Which AV(s) did you use before Avast..?

[Goldfisch]

- Windows 7 Professional (64 bit). Window's own Fire Wall is running. Last Windows security update is Windows antimalware tool v5.88(KB890830) on 2021-04-14
- Not aware of any. Adblock Plus and Ghostery are running.
- I think Kaspersky, but that was years ago and since I installed Avast their FW was running without any problems.

[Asyn]

First, be sure to get rid of all remnants of any prior installed AV(s)..!!
-> https://support.avast.com/article/11/

Then:
1. Download Avast Premium Security: https://files.avast.com/iavs9x/avast_premium_security_setup_offline.exe
2. Follow instructions: https://www.avast.com/uninstall-utility (Run this tool for all prior installed Avast versions..!!)
3. Reinstall Avast with the downloaded installer from point 1.
4. Reboot.

[Goldfisch]

Worked smoothly, thank you very much!

[Asyn]

You're welcome.