Dear All, Background information: Exchange 2007 SP2 (Single Box with CAS, Hub, Mailbox Roles) Windows 2003 SP2 Outlook 2007 Client SP2 I have enabled the Outlook Anywhere on the Exchange Server, The "DefaultAuthenticationMethod", "ClientAuthenticationMethod", and "IISAuthenticationMethods" are all set to "NTLM", However, when running "Test E-mail AutoConfiguration" on Outlook 2007, it showing the Protocol: Exchange HTTP Server: XXX.abc.com SSL: Yes Mutual Authentication: Yes Availability Service URL: Https://autodiscover.abc.com/ews/exchange.asmx OOF URL: https://autodiscover.abc.com/ews/exchange.asmx OAB URL: https://autodiscover.abc.com/oab/01283028309.../ Auth Package: Unspecified Certificate Principal Name: msstd:*.abc.com The problem is the "Auth Package" is always showing as "Unspecified", and Outlook client will always reconfigure itself through autodiscover, and set the "Proxy Authentication Settings" back to "Basic" although updating it manually back to "Ntlm". I have tried to recycle the IIS application pool --> MSExchangeAutodiscoverAppPool without any luck. Also executed the without any help: set-outlookanywhere -server name -clientauthenticationmethod ntlm set-outlookanywhere -server name -IISAuthenticationmethod ntlm Set-OutlookProvider EXPR -CertPrincipalName "msstd:post.ourdomain.edu" Your help will be much appreciated! Roy

Hi Are you trying to configure Autodiscover? See this link to understand and configure the Autodiscover , http://www.shudnow.net/?s=autodiscoverserviceinternaluri Jonas Andersson MCTS: Microsoft Exchange Server 2007/2010 | MCITP: EMA 2007/2010 | MCSE/MCSA Blog: http://www.testlabs.se/blog

Hi Jonas, Thank you very much for your help, it is a great article. I found out the problem was related to the "Outlookprovider" configuration. After execute set-outlookprovider -server $null The problem was resolved, and the Auth Package showing "NTLM" without any further configuration. It was really a pain we have to go through all these strange configuration to get it working. Thanks again. RoyRoy

HI Jonas, Just wondering if you got any good link about the following topics: 1. ISA with Exchange 2007/2010 2. How does Exchange 2007/2010 work with Multiple CAS environment. e.g. How does user know who CAS they should use manually or through autodiscover service if it is a multiple location/countries deployment. Thanks RoyRoy

Hi 1. ISA 2006 works with Exchange 2003/2007/2010 2. Use CAS array and point ISA to the array Hope this works for youJonas Andersson MCTS: Microsoft Exchange Server 2007/2010 | MCITP: EMA 2007/2010 | MCSE/MCSA Blog: http://www.testlabs.se/blog

Resources: Using ISA Server 2006 with Outlook Web Access Configuring ISA Server 2006 for Exchange 2007 Client Access Publishing Exchange Server 2007 with ISA Server 2006 Using ISA Server with Outlook Web App Transitioning Client Access to Exchange Server 2010James Luo TechNet Subscriber Support (http://technet.microsoft.com/en-us/subscriptions/ms788697.aspx) If you have any feedback on our support, please contact tngfb@microsoft.com