Hi,

Using Exchange 2013 CAS servers in Loadbalancer high availability setup configuration.

Our users are having intermittent OWA access issue when they accessing it from IE and Chrome browsers?

Any help.

Hi,

What errors do your users get when the issue is present? Can they load OWA but not log in or do they get a failure when trying to load the OWA login page?

Can you test each CAS server in turn by removing all but one from the load balancer and testing out OWA?

Also, check the application event log on each CAS server.

What type of load balancer are you using? Can you find a correlation between the events users are reporting and any failovers that have happened on the load balancer?

Thanks.

Hi,

It's an Intermittent issue. "Page cannot be displayed" is the error message when hit OWA URL through browsers.

we are using F5 hardware loadbalancer. 

Hi,

Error message getting as after click our OWA URL.  

This error (HTTP 403 Forbidden) means that Internet Explorer was able to connect to the website, but it does not have permission to view the webpage.

Check that the users are connecting to https://mail.domain.com/owa and not http://mail.domain.com/owa. 

Also check that the load balancers are configured to direct traffic to port 443 rather than 80. If you have an HTTP to HTTPS redirect in place then check this is working on each server.

If this is all ok then check the OWA IIS virtual directory permissions on the CAS and MBX servers are correct.

Thanks.

Found One of the CAS server virtual directory is not working. https://localhost/owa link is not working within this particular CAS server.

When I edit Site Bindings from IIS Default website, https 443 port unable to bind without any * 

though i choose All Unassigned, but that binding still say https  port 443 IP Address *

How to bind it without * port 443 

Have you checked that the certificate is imported with the private key (user the certificates MMC snap in) and this certificate is assigned to the IIS service (Get-ExchangeCertificate)?

Thanks.

Hi Mark,

Found that problem in IIS authentication type and then it's fixed the issue on that particular CAS Server.

Thanks for your response.