New version 25.5

Avast Free Antivirus / Premium Security
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1

Hello,

Please welcome the version 25.5 of Avast AV released on May 27th 2025
This announcement is too late to even apologise for the delay. We hope that you are enjoying the new version and we are more than keen to hear your feedback (about the product, not the late announcement - sorry about it)

Major public announcement:

  • bug fixes to increase product stability and product performance

How to install:

  • Update from your existing Avast version via Settings → Update → Update program
  • Or you can download and install files:

Online installers (recommended):

Offline installers:

2

It would be interesting to get details of what changed as there are many posts in the Community Forum of issues with 25.5.

Noticeably users settings being changed.

3

Thanks for the release and release topic :slight_smile:
Hopefully, more in-time post next time :wink:

2 Likes
4

Any info about Scam Guardian?

5

After the update, Chrome has become extremely slow and laggy on Windows 10 64-bit. Please fix it.

1 Like
6

Released on May 27th. Post created on June 16th.

Why the delay?

7

Probably because they cannot post, because new “upgraded” forum introduced Cloudflare errors.

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I haven’t seen any of those for a long time (kiss of death).

9

Absolutely. I got a 403 error straight after reading your post :frowning:

1 Like
10

Hello everyone, I have a question:
I have configured Avast to update manually.
The UI was at version 1.0.838 until yesterday.
When I checked today, the UI was at 1.0.839.
My question is, if my Avast is configured for manual updates, why was the UI updated without my permission? :thinking:

Thank you, I’ll wait!

11

Hello, I would like to report a translation error in Brazilian Portuguese. The image below shows where the error is.

image
image588×198 11 KB

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Can anyone answer this question for me?

13

Avast often does whatever it wants. I think Devs like it that way.

User preferences and previously explicity enabled or disabled settings and components just suddenly change.
When we complain it gets ignored.

1 Like
14

Hello, another bug was found in the Avast interface for the Brazilian Portuguese language, as the image below shows.

image
image1075×616 78.1 KB

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Hello, I believe that Avast has something to do with this problem.
I don’t know how to solve this problem. I’m using version 25.6.10221a (build 25.6.10221.939)

image
image1040×521 12.3 KB

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Well not being able to read the error message other than the last bit ERR_QUIC_Protocol_Error, when QUIC is a connection method. You don’t say what browser you are using and I don’t think this is related to the 25.5.xxxx version, so should probably be in its own topic.

Other than do a quic (excuse the terrible pun) error search

Which I did may help you pin it down.

That said I just visited the site without issue using Firefox, and entered the forum, that said any member function I wouldn’t be able to test, not having registered. That is a step too far for me testing.

EDIT: You might want to try disabling the Avast Settings > Protection > Core Shields > WebShield > QUIC/HTTP3 scanning. This was on when I checked the site.

b10110
b10110850×567 135 KB

1 Like
17

Hello, the browser I’m using is Google Chrome, latest version.
I searched for “ERR_QUIC_Protocol_Error” and found that my browser supports this technology. Look what I found.

1 Like
18

I’ll try to disable it and test to see if it works.
But we know that Avast checks this option for more security.
I’m going to disable it to do some tests.

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@DavidR Hello, I just finished testing for 5 minutes disabling the option you showed in Avast. Everything worked normally.

When I re-enabled the option, as soon as I opened the website to visit the site, the QUIC error appeared.

In conclusion, I believe it is AVAST.

20

Well it worked for me, but I wasn’t using Chrome.
So there are two possible players in this game.

Three if you include the site and does it 100% follow the QUIC standards. However the areas I went/permitted to go worked with QUIC enabled and using Firefox.

1 Like