Problem when switching form Avast Internet Security back to Avast Free Antivirus

[REDACTED]

My Avast Internet Security is about to expire, so I went back switch it back to Avast Free Antivirus in the Subscription tab. After that, I waited for the process to finish, but after half an hour it still stuck close at the finish. So, I go check what is happening, turns out the update part is stuck at this part:

launching executable file:C:\Program Files\AVAST Software\wsc_proxy.exe\ svc\ unregister\ firewall

I try end process wsc_proxy in the Task Manager, but it said access denied and I can't close it. Restarting the pc cause a my internet ip address to be block by Avast and enable to use the internet. I manage to fixed that problem by System Restore, but the root of the problem still exist.

So, any help?

Avast version 17.9.2322 (build 17.9.3761.0) Window 7 Ultimate 64-bit

[Asyn]

1. Download Avast Free Antivirus: https://files.avast.com/iavs9x/avast_free_antivirus_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.