Exchange 2016 - Namespace cause external cannot access to OWA

Question

I need some advise on my current configuration for exchange 2016 server.

Right now, I'm having problem to access the OWA of exchange externally.

Can this be caused by the design of my URL?

My server hostname is exchange01 And all of internal and external URL used exchange01.company.com

Internal DNS - added A records for exchange01 and autodiscover.company.com that point to my internal exchange serverIP.

External DNS - added A records for autodiscover.company.com and pointed to public ip of exchange server, A records for exchange01 and pointed to public IP.

Is there anything missing in my configuration or is the URL that caused DNS confusion?

Hope anyone can assist! Thanks!

Answer 1

Hi,

Could you please provide your Exchange Server Build by typing the cmdlet in the EMS: Get-ExchangeServer | fl Name,Edition,AdminDisplayVersion

added A records for autodiscover.company.com and pointed to public ip of exchange server, A records for exchange01 and pointed to public IP

Please capture details about your A record configuration. The A record should be accordance with the URL of external OWA URL.

To access OWA and send/receive messages on it externally, we need configure A records, MX records, Certificates, Firewall Ports and external OWA URL.

Please check the following questions:

1. When you accessed other services (ECP, ActiveSync etc.) externally, were they affected?

2. Is the OWA Virtual Directory configured correctly? We can check it by using the cmdlet “Get-OWAVirtualDirectory | fl” in the EMS.

3. Did you configure SSL Certificates? Please install a certificate that includes external OWA URL in the server.

   More details about creating and installing certificates: https://www.digicert.com/csr-creation-ssl-installation-exchange-2016.htm enter image description here

4. Whether you open the firewall ports for Exchange Server?

   More details about Network Ports: https://docs.microsoft.com/en-us/exchange/plan-and-deploy/deployment-ref/network-ports?view=exchserver-2019

5. Were there any issues reported on the OWA page when you accessed it?
6. Were there any errors in the Event Viewer after you accessed OWA?
7. Please check the IIS Logs(Log path is %SystemDrive%\inetpub\logs\LogFiles by default). enter image description here

8. Did you set load balance? Please add the public FQDN and IP in the DNS Host files.

   If you want to know more details about it, please connect to the URL: https://practical365.com/exchange-server/testing-connectivity-and-dns-changes-with-a-hosts-file/

More details about Mail flow and Client Access: https://docs.microsoft.com/en-us/exchange/plan-and-deploy/post-installation-tasks/configure-mail-flow-and-client-access?view=exchserver-2019

Best regards,

Ivan Wang