Microsoft Exchange Security Certificate

Can you please explain more about what you are trying to do and what environment you have, then I can give you some information to hopefully assist you.
What version of Windows Server do you have?
What version of Exchange do you have?
Thanks
Alan

You can buy a cheap certificate from https://www.godaddy.com/ssl/ssl-certificates.aspx
You Exchange must be 2003SP2 and above
If your exchange is 2007 my advice is to buy a 5domain certificate in order to avoid extra configurations on your exchange.

I am trying to sync a windows mobile 6.5 with the exchange server at work. The exchange server has certificates and every other smartphone in the company will sync with the server. My phone has certificates but nonetheless when I try to sync I get the following error message.

The security certificate on the server is not valid. Contact your Exchange Server administrator or
ISP to install a valid certificate on the server.
Support code: 0x80072F0D

I have had limited success in getting the device to sync with the Exchange Server via cable, once I installed personal and intermediate certificates issued by the company. I am unable as yet to sync via internet. Perhaps this is because of the difference in the Outlook Web Access host address and the Outlook Web Access Proxy Host Address.

We are using Client Access server operating system version: Microsoft Windows NT 6.0.6002 Service Pack 2 and Microsoft Exchange 2007.