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How can we use extern & local url with SSL certificate ?

SA-IT asked
Last Modified: 2014-08-14

I am busy to install a new Exchange 2013 server but I still get an error with certificate.
I have 2 urls (one extern url to connec to Exchange remotely and one local url.)
I successfully installed my SSL certificate for the extern url but I still get an error locally when I start Outlook because Outlook is asking for local certificate.
I don't understand what is wrong in my configuration because on my old server I only used the SSL certificate for extern url and I hadn't got any problem  locally and externally.  The certificate was OK in both case.

Do you have any idea about the problem ?  Problem in the configuration of Exchange 2003 (different than 2007) ?
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If using a certificate the certificate always looks at the URL it is assigned to.
So let's say the certificate is requested for the webmail.externaldomain.com then when you browse to that site, the certificate is oke because it is the same as the server name you typed in.

If e.g. you use webmail.internaldomain.com the certificate isn't correct anymore and the name it doesn't represent the URL you just typed in.

It may be because the certificate name doesn't match the local server name. Some applications will accept this, but others will complain, because technically, it's an error. You can only have one cert per site, so it might help to set up internal DNS records for the same external server name, pointing to the local IP address. That way, you can use the same server name internally and externally. Which is what most of us end up doing.

Unless you tried that?
Most Valuable Expert 2014

The best practise with Exchange 2013 is to use the same URL for internal and external traffic.
Use a split DNS system to have the external name resolve internally to Exchange. No internal only URLs used.
This also helps the end users as they only have to remember one address.




Yes my external url is like webmail.xxxx.xx and I have a local server name.  I also have a DNS record for webmail.xxx.xx which point to the local server name (locally). (it is the same domain locally & externally)
It was perfectly working on my 2007 exchange and I hadn't got any problem of certificate.
Is it a limitation with Exchange 2013 ?
Most Valuable Expert 2014

There is no limitation, but you do have to configure Exchange to use the external host name. That includes the crucial Outlook Anywhere configuration.



When do I need to make this change in Exchange 2013 ?
Most Valuable Expert 2014
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