Skype for Business client 2015/2016 not responding when Audio/Video or desktop sharing call happens.
Recently I was working with client who has multiple users complaining about Skype for Business 2015 / 2016 clients not responding, when they receive or make audio call / video call / application sharing session.
User has to restart the Skype for Business program. Like below screenshot.
Skype for Business client works fine only for Instant Message but not for A/V or application sharing sessions.
- First thing I did is to check USB devices and removed all devices and make audio call but issue wasn’t resolve.
- Windows OS application Event log did not gives any pointer.
- Then, I reproduce issue and capture UCCAPILOG and Wireshark Pcap Network capture, Uccapilog did not show candidate exchange and media setup before that Skype for Business client hung and shows not responding. The only option available is to restart Skype for Business client.
- Did not see candidate exchange, means before media flow starts, client hung which eliminate the server or network side issue.
- Same users account can use Skype for Business client for Audio/ Video / Application sharing modality using different computer, means something is wrong on client computer.
- Checked user’s computer to see running processes, found “Lavasoft” process running in task manager under process. And when checked installed software in Control Panel > Programs and Features > “Web Companion” software installed and running, this software is from Lavasoft.
- When exit the Web Companion software from task bar, made call however still audio/video/application sharing did not work, then finally uninstalled ‘Web Companion’ software from user’s computer and then made call, this Audio/Video/Application Sharing starts working using Skype for Business client without hung. JIs Ad-Aware Web Companion software blocking media stream?
Web Companion software has network and web protection, which are filtering network traffic and intervene with Skype for Business process (Lync.exe) which hung the Skype for Business client. Skype for Business client did not like any intervention from Web Companion.
- Basically, Lavasoft Web Companion has new security feature in Ad-Aware Web Companion to scan and eliminate malicious content/advertising in HTTPS traffic, including content injected by internet proxies installed on the computer.
- I think, this software is a TCP-Hijacker that allows the software to redirect the tcp streams, which is actually preventing Audio/video/Application sharing stream and hang client applications.
Resolution is pretty simple, uninstall Ad-aware Web Companion software completely, which actually remove everything install along with Web Companion and your Skype for Business client will work fine.
Sometime, I see uninstalling Web Companion does not resolve above issue because uninstalling Web Companion software remove added registry keys, in that case you need to deleted Lavasoft / Web Companion registry keys.
Note: You must take Registry backup before deleting registry keys.