O365 Mail & Teams Connectivity Issue


We are currently implementing Zscaler in our network
we have started noticing some users complaining that their outlook mail & Teams app just does not respond when Cisco AnyConnect is connected along with ZCC client
Cisco AnyConnect is in split tunnel mode.

I have noticed that there are a few topics related to this and all the suggestions and instructions are already in place like One-click-configuration is ON, o365 URL’s have been bypassed from the PAC (only the 3 login URLs are forwarded to the SIPA).

But nothing works, we have also tried pointing to another Zscaler DC, same result, we tried changing DTLS to TLS, same result…

If this has worked for anyone in here, request your support in letting me know what was changed to resolve the issue…

many thanks in advance.

Definitely open a support case. However, one issue I once came across with AnyConnect is that it will sometimes block access to a local proxy running on the loopback port. If you’re using the Zscaler Client Conenctors using tunnel-with-local-proxy mode, you may need to disable this on the AnyConnect side. See this: Heads up: Zscaler App in local proxy mode and Cisco AnyConnect VPN Client