[Bug] Avast is changing/corrupting downloads

Avast Free Antivirus / Premium Security
1

Well, it’s hard to say, but I lost quite some hours to figure out that the culprit is Avast.

  1. I’ve tested Firefox, Chrome, Opera and Edge.
  2. I’ve tried with and without any download manager.
  3. I’ve tried disabling Windows SmartScreen filter.
  4. I’ve tested three different networks (one ethernet and two WiFi).

Only disabling Avast will allow me to download executables, .msi and archive files that match the hash in the download site.
I’m on Windows Insider Preview 14942 (x64).

2

No problems on build 14936. There are many reported problems on the version you are using when using an AV other than Defender.

3

i wrote about it here as well, with firefox…

4

Bug is still around. Tested today with Notepad++. Download with Avast on gives and error (file corruption).
Disabling Avast and everything goes fine.

5

Hello,

This issue is known and we are working on a fix. Currently the way to download files uncorrupted is to turn off Web Shield. I’m sorry for Your troubles.

Libor

6

Windows 10 Insider Preview builds are only for testing purposes.
So yes, you can/should expect bugs, unstable systems or worse :wink:

Greetz, Red.

7

Same problems here with 14942.
After install of 14946 most of my problems are gone.
Only problem left (until now) are download problems with Windows update with updates for Windows Defender.
Problem gone after disabling Avast.

8

Thanks for acknowledging it. At least, I don’t have to invest more time on discover what is wrong :slight_smile:

9

After install of 14951 still download problems.
Problems gone after disabling Avast

10

I have reverted to 14931 (slow cycle of updates) and everything is fine.
Most probably the multiply instances of svhost processes are behind the issue (but this is just a guess).

11

Ticket created for this issue:
#563093 Download problems with W10 Insider Preview Build 14951 for PC
https://support.avast.com/support/tickets/563093

Answer from ticket:

I discussed this problem with our developers and they informed me they are currently working on a fix. The fix version of Avast should be released soon.

12

Known issues for PC in build 14955
If you have a 3rd party antivirus product installed on your PC – your PC might not be able to complete the update to this build and roll-back to the previous build.
Read more at https://blogs.windows.com/windowsexperience/2016/10/25/announcing-windows-10-insider-preview-build-14955-for-mobile-and-pc/#IVVmeYJlbdkbOO7M.99

13

I have upgraded to 14955 and the download problems still persists

14

Looking at all the reported problems with Windows 10, I start to wonder what the worse Windows release is/was.

10 or Vista.

15

You are looking at problems in Preview Builds.
There aren’t any problems in the latest stable release. :slight_smile:

16
There aren't any problems in the latest stable release
Not? Muhahaha, if I would name them all here this post would be huge !

There is no stable release as all versions released have many bugs.

17

After install of 14959 still download problems.
Problems gone after disabling Avast

18

Build 14936 was the last build that had no problems with 3rd part AV’s.
Microsoft sitll hasn’t addressed the problem. That’s one way to force you to use their own Defender. :frowning:

19

After install of build 14965 still download problems.
Problems gone after disabling Avast

20

Thanks for reporting. We need to wait…
The bad is that MS seems not even list the problem in the known problems.
http://www.askvg.com/new-update-build-of-windows-10-technical-preview-now-available-for-download/