We are company manufacturing cameras for medical use. Starting Saturday, we have fielded multiple customer calls where the video would not display unless AVG or Avast are uninstalled or in passive mode.
We tried even with a regular webcam and the issue replicates every single time. We are using amcap for testing.
Please escalate the issue. It is disruptive to potentially millions and is easy to reproduce (hence fix)
Maybe they have a common root however I would say they are different issues as nothing eliminates this issue other than uninstalling or setting complete passive mode. Also there is no network involved in this scenario, the streams are displayed from cameras (even webcams) installed locally via USB
Agreed, in my case, there’s no issue with viewing video locally, via Yawcam, on the PC with the connected USB webcam, Avast installed, and all its shields active. The problem occurs in stream viewing on remote PCs that have Avast installed and Web Shield enabled.
I agree. Seems to be related to DirectShow indeed. And as AVG an AVAST share some code, it happens to both. Maybe a developer will see this and do a quick test, I am surprised there aren’t more reporting this. is likely that they do not know the AV is killing their webcams.
Since the update this past weekend, around 4/29/17, both Avast and AVG have blocked users’ webcams on our platforms. This has happened for over 20+ users with Windows 7, 8.1, and 10. I have tested and confirmed in-house with reliable results. Adding exceptions or testing many settings has not worked. Only setting Avast to passive mode has worked. This same issue happened with AVG, a company purchased by Avast last year. This seems to be a common thread here. Please work on this. I called the helpdesk and they wanted premium support for a clear issue with the program. Other anti-virus programs have worked well.
Troubleshooting notes:
Added folder exception for the entire AppData\Local folder.
Added program exception for .exe in Cyber Capture.
Added program exception for .exe in Hardened mode options.
Added URL exceptions
Turned off File Shield, Web Shield, and Mail Shield under Protection → Anti-virus.
Turned off Cyber Capture.
Firewall options are a paid feature. Maybe firewall is not active in free version.
Tried a manual join of the .exe instead of launching through our website. No webcam.
There is an option called automatic port scan detection. No access to this due to free version. Avast UI → Protection → Firewall → Settings → Advanced → Uncheck “Enable automatic port scan detection”.
Disabled behavior shield.
I killed Avast in task manager, no change. (self-defense mechanisms likely prevented this)
Disabling Avast on startup, then restarting provided no change.
The Avast service was still running in the background.
The Avast behavior scanning service was still running in the background.
Components → File System Shield → Customize → Added exclusion exe folder.
Components → Behavior Shield → Customize → Added exclusion exe folder.
Components → Web Shield → Customize → Added exclusion to .exe.
Turned Avast to Passive Mode. Worked following prompted restart.
Not working anymore after turning Passive mode to Active and restarting.
Added the two removed exceptions back in, but no change.
Re-activating the disabled processes did not make any changes.
Turned discovery of suspicious files to “ask” instead of disconnect.
Added script exclusions.
Turning off HTTPS scanning did not work.
Restart. Webcam not working.
Turned off script blocking.
Smart scan (Explorer) – Heuristics off.
Tried redirecting the ports under Troubleshooting → Redirect Settings. Platform would not even launch under 443 or 80 redirect.
Set file system shield settings to ask when encountering a suspicious program
Plugged in and attempted to use a Logitech C270 external USB webcam
I turned Avast back to passive mode and restarted. This worked.
Turning the passive mode to active mode caused the external webcam to no longer work.
This issue appeared for other users with TV ;capture cards: https://forum .avast .com/index.php?topic=201635.0
Also, https://forum .avast .com/index.php?topic=201702.0
5/3/17 Notes:
Updated Avast in the AM as there was a patch – no change after restart.
Followed recommendations in this post: https://forum .avast .com/index.php?topic=201645.0
-Scan traffic from well-known browser processes
-ignored redirecting local communications
Called Avast support: 1-844-340-9251
Demonstrated the issue to the helpdesk. The helpdesk member, confirmed that he thought Avast was the root cause, but stated Total Care would be needed to continue.
I should note that in my testing of the issue, the webcam continues to work in Windows 7 using Silverlight and Win 10 using the built-in Camera app. This is despite the webcam not working in the video conferencing platforms.
port COM device , port USB device , More than one Network card and/or devices (NAS , Tuner TV , particular cam or alarm)
Already a lot of problems encountered with the web shield of the latest version of avast
Pending that avast restore order in all that, it seems that they proposed a version beta ???
It almost looks like the web shield functions as a (failing) firewall
It was reported on Windows7 (WIndows update enabled) with a Logitech C310 and a Sweex webcam
Today I tested it with a newly installed Avast Free with default settings
The issue can be reproduced with the old AmCap.exe from the Windows DirectX9 samples (I can’t find exe on the net, its size is 6963 bytes and the timestamp is 2001.11.05)
The preview doesn’t appear, and displays a dialog with error code 0.
These programs are used thousands of users and have a digital sign - OMT-LIDER, TOV.
Since April I have gotten many complaints from my users with one issue: Avast blocks a webcams access for my programs. Why?, before we didn’t have any problems with Avast!
I produced that situation and tested the Avast Free Antivirus 17.4.2294 (build 17.4.3482.0, virus version 170505-2) in our lab. My users were right - the problem in Avast.
You can test my programs in your lab too. These programs are free for usage and can be gotten by using those URLs, see above.
Viktor
We got same issue, I am Sr. Tech Support for Video Relay Service company for deaf and hard of hearing users, we got several reports from our clients about local screen being not displayed with our videophone application since last week. We are encouraging our clients to uninstall Avast or enable Passive mode.
For Windows 10 only, interesting part is after uninstalled KB4015217 under Windows Updates and this resolve our local screen issue.