i have configured exchange server 2010 on windows server 2008 and my email server is: mail.centors.com and my user account is user@centors.com when i tried to configure outlook 2010 to add this exchange account i am getting the error: The connection to Microsoft Exchange is unavailable. Outlook must be online or connected to complete i restarted the service **microsoft exchange attendant services** but still keeps getting same error. please advise how to fix this issue with little details since i am a developer not a system admin.

You can verify the connectivity of the computer with the exchange server by various methods: Have you tried to configure an another account to check the behaviour? Check the same account from a different computer too 1. Try to access the webmail url from the machine and see the result 2. Are you able to ping to the cas array or cas server? 3. Have you tried to telnet to the cas array or cas server or to owa url (eg. telnet url 443) If you are having problems here, correct the connectivity. Firewall may be a reason which is not allowing the connectivity. Regards from ExchangeOnline | Windows Administrator's forums

can you please tell me how to verify those steps, since i am not a system admin. please have a look at my configuration, if i am missing something http://social.technet.microsoft.com/Forums/gu/exchangesvrgeneral/thread/30b9a210-346b-4cf0-a58a-f3cced27b630

Are you able to connect to the server through telnet? Open command prompt (Run as Administrator) and run the command telnet mail.centors.com 110 If you are unable to connect, disable all firewalls at server and client and try again. You have to correct this first to proceed furtherRegards from ExchangeOnline | Windows Administrator's forums

i am getting the following response: +OK <17260.1348662740@p3plpop07-02.prod.phx3.secureserver.net> i guess that means there's no problem with the connection to the mail server. but i read in some place that the machine that contains the outlook should be member of the domain of exchange. any other advises ?

On Wed, 26 Sep 2012 11:58:18 +0000, ManU PhiliP wrote: >Are you able to connect to the server through telnet? > >Open command prompt (Run as Administrator) and run the command telnet mail.centors.com 110 > >If you are unable to connect, disable all firewalls at server and client and try again. You have to correct this first to proceed further His problem is that he has an Exchange server but he's set DNS to use his ISP's mail system. --- Rich Matheisen MCSE+I, Exchange MVP --- Rich Matheisen MCSE+I, Exchange MVP

On Wed, 26 Sep 2012 11:58:18 +0000, ManU PhiliP wrote: >Are you able to connect to the server through telnet? > >Open command prompt (Run as Administrator) and run the command telnet mail.centors.com 110 > >If you are unable to connect, disable all firewalls at server and client and try again. You have to correct this first to proceed further His problem is that he has an Exchange server but he's set DNS to use his ISP's mail system. --- Rich Matheisen MCSE+I, Exchange MVP --- Rich Matheisen MCSE+I, Exchange MVP