Error code Connectivity_ICEWarn 0x80020 and Connectivity_ICEWarnEx 0x90

Interpreting Error Codes: Connectivity_ICEWarn 0x80020 & Connectivity_ICEWarnEx 0x90

These error codes are related to Interactive Connectivity Establishment (ICE), commonly used in Microsoft Teams, Skype, and VoIP applications. They typically indicate network connectivity issues affecting real-time communication.

Possible Causes & Fixes:

🔹 Firewall or Proxy Restrictions – Ensure WebRTC, STUN, and TURN traffic is not blocked.
🔹 NAT Configuration Issues – Use a VPN or configure port forwarding for better connectivity.
🔹 Corporate Network Policies – Contact your IT admin to allow the required ports and protocols.
🔹 Internet Connection Issues – Test with another network to identify local connectivity problems.

For more troubleshooting tips, visit:
🔹 ReminiGeek
🔹 NetworkVents
🔹 TMWHTS

Hi LightInTheDark ,

0x80020 might be related to a DNS resolution failure from the client, e.g. the client is not able from its source network to get name resolution completely right.

And the 0x9000 might mean that it is malformed...

Check out this: 

• https://digitalbamboo.wordpress.com/2013/09/12/how-to-find-lync-ice-connectivity-failure-error-codes/
• https://www.msxfaq.de/skype_for_business/technik/icewarn.htm

• What client are you using? Windows(/Mac/Mobile/Browser/Linux)?
• How many are affected?
• Did you try it from another computer?
• Did you try it from another network, e.g. non-corporate network, test network/direct Internet link/LTE or else?
• Are all Office 365 IPs and URLs in the white listed on the FW and proxies?
• Is the client traffic via the Internet Breakout anyhow intercepted? E.g. fancy FW/proxy features which might break encryption, delay ... etc.