Avast WEBforum

Consumer Products => Avast Free Antivirus / Premium Security (legacy Pro Antivirus, Internet Security, Premier) => Topic started by: 창묵 on July 11, 2016, 02:42:41 AM

Title: [fixed] Firewall blocks hyper-v
Post by: 창묵 on July 11, 2016, 02:42:41 AM
Hi, all
I'm using Avast premier and also using Hyper-v on Windows 10 64bits.

I made internal virtual switch, using by Virtual Switch Manager from Hyper-V Manager, to connect internet from my guest OS.
and I turned ICS(Internet Connection Sharing) on, but firewall blocks all internet connections from my guest OS.

But I clearly remembered that I could connect to internet by above settings only.
I reinstalled avast premier several times, but nothing is resolved...:(

Sorry for my English. It's not my native language... but I hope you know what I'm saying.

Please help me, I don't want to turn firewall off whenever I use my virtual machine.
Title: Re: Firewall blocks hyper-v
Post by: Filip Braun on July 11, 2016, 01:07:25 PM

Thank you for reporting this, however we were not able to reproduce the issue.
We are able to connect to internet from guest VM even when Avast Firewall is ON.

Can you please share more info about your Hyper-V setup?

Thank you,
Title: Re: Firewall blocks hyper-v
Post by: 창묵 on August 03, 2016, 09:36:19 AM
Sorry for my delayed comment. Please refer below answers.

1. Why are you using internal switch for accessing the internet? External switch should be suited for this.
  -> I want to use the internet host and guest OS at the same time. because I only use guest OS's internet connection for compatibility test on Windows 7 and Internet Explorer 9 environment. But when I use External switch, host's internet connection is broken... Is it possible using the internet on both side at the same time with External switch?

2. Where did you turn on the ICS? On host or in guest?
  -> I did turn on the ICS on host. When I only turn the host's AVAST Firewall off, All problem is resolved.

3. Please share your Virtual Switch manager settings for more info. Possibly screen shots.
  -> I want to attach image files, but don't know how do it.
       I've made Internal switch, and shared my ethernet adapter with Hyper-V Virtual Ethernet Adapter.
       Hyper-V Virtual Ethernet Adapter is created by Hyper-V after I made new Internal Virtual Switch.
       IP address of Hyper-V Virtual Ethernet Adapter is and the guest's IP address is and the guest's Default gateway is
       At last, I've turned on the ICS on host computer.
       I've touched nothing, without above mentioned settings.
Title: Re: Firewall blocks hyper-v
Post by: Eddy on August 03, 2016, 09:44:33 AM
I want to attach image files, but don't know how do it.
Below the box where you type your message > Attachments and other options
Title: Re: Firewall blocks hyper-v
Post by: 창묵 on August 03, 2016, 12:00:12 PM
Oh, Suddenly all problems are resolved!

Today, I downloaded avastclear.exe and execute it to clear avast from my computer.

It was executed on Windows Safe Mode and it removed Avast clearly!

I reinstalled Avast Premier again... and then suddenly All things are working properly!!

I assume that some Avast settings in my computer went wrong. and Uninstalling Avast from Windows Control Panel is keep that settings on system.

And I still don't know why the settings went wrong... The problem was started after I formatted my disk and reinstalled Windows 10...

Anyway, Thank you for replies to solve my problem.

Best Regards.