Hi all, Environment: - Exchange 2010 SP2 RU3 - 2 servers with 3 roles: Mailbox, Client Access and Hub transport - Hardware load balancer is used. - DAG configured - Outlook anywhere Enabled. Basic Authentication - All databases belong to the same Client Access Array - Users have same UPN as email address When a user mailbox is moved from a database to another one, user get a prompt in his Outlook 2010 asking for credentials. I think this should be transparent to end users. The source and target mailboxes belongs to the same Client Access Array. This happens to users with Outlook cache enabled and Outlook without cache. Is this normal behaviour? Or is caused do tue Outlook Anywhere authentication? Thanks in advance

Hi, If you have outlook anywhere enabled, often the login box will prompt for credentials, as the outlook client switches from a TCP to a RPC/HTTP connection. To troubleshoot this, uncheck Connect to Microsoft Exchange using HTTP in outlook clients and do a moveRegards from www.windowsadmin.info | www.blog.windowsadmin.info

Thanks ManU for your response, Not always ask for credentials to connect to Outlook Anywhere, some times in the credential windows appears the mailbox server name... I think that uncheck "Connect to Microsoft Exchange using HTTP" is not an option, because I have about 2000 mailboxes.... When I do maintenance tasks, I cannot change this parameter

Hi, Have you enabled Kerberos authentication in your exchange servers? CAS array, by default won't support Kerberos. So configure kerberos authentication for the CAS Array and test the behaviour then. I found a good refernce here: http://setspn.blogspot.in/2010/08/exchange-2010-enable-kerberos-on-cas.htmlRegards from www.windowsadmin.info | www.blog.windowsadmin.info

No, I havent enabled Kerberos authentication on CAS. Must I eneble ths to solve this behaviour? Thanks!

Hi SKM12, Sound like some misconfiguration in your HLB. What method to you have set for persistence and what is the timeout? Martina Miskovic

Hardware Load Balancer configuration: TCP 443: Persistence: Source IP 1200 seconds . Session Timeout:12h TCP 80: No persistence TCP 110: No persistence TCP 995: No persistence TCP 135: Persistence: Source IP 1200 seconds . Session Timeout:12h TCP 60200: Persistence:Source IP 1200 seconds . Session Timeout:12h (CAS STATIC PORT) TCP 60201: Persistence: Source IP 1200 seconds . Session Timeout:12h (CAS STATIC PORT) When I move a mailbox from database, sometime asks for users credentials, sometime not.

Another strange behaviour (may be related with the problem on this post): Randomly, this infamous warning appears to some end users: "The Microsoft Exchange Administrator has made a change that requires you quit and restart Outlook"

Hardware Load Balancer configuration: TCP 135: Persistence: Source IP 1200 seconds . Session Timeout:12h TCP 60200: Persistence:Source IP 1200 seconds . Session Timeout:12h (CAS STATIC PORT) TCP 60201: Persistence: Source IP 1200 seconds . Session Timeout:12h (CAS STATIC PORT) When I move a mailbox from database, sometime asks for users credentials, sometime not. 1200 seconds it too low. Many HLB vendors recommend to have it set to 7200, but check the manual for the HLB you are using. Martina Miskovic

Thanks Martina for your quick response!! We are using Cisco CSS, and I cannot find a configuration guide to load balance Exchange services, so we have configured the timeout according to other HWLB. Do you think that asking for credentials when mailbox movement may be realated whit HWLB misconfiguration (timeout)?

Do you think that asking for credentials when mailbox movement may be realated whit HWLB misconfiguration (timeout)? Yes, that's exactly what I am thinking. I've seen it before, so... I have no experience with Cisco CSS so I can't help you there but do change the settings and see if that helps.Martina Miskovic

I could have reproduce the mailbox movement issue in a lab environment. In this lab there is only a CAS and two mailboxes in a DAG, and HWLB is not used. Same issue on lab without HWLB, I am frustrated :(

I'd suggest you collect network trace log for further analysis. Hope it is helpful.Fiona Liao TechNet Community Support

Traces logs does not any warnings or errors.

I really think Exchange ask for user credentials due to Outlook Anywhere. if I disable Outlook anywhere, credentials window does not appear... but is very strange this behaviour. When the mailbox is moved it is disconnected for a few seconds. I understand that Outlook gets disconnected and tries to connect by HTTPS...

If disabling Outlook Anywhere, Outlook will connect via TCP/IP internally. I am suspecting the issu is caused by a firewall in front of your CAS server? Try to reproduce the issue via clicking Send/Receive button, or enabling the Out of Office settings. It would help us isolate the fault. Thanks. Fiona Liao TechNet Community Support

Send/receive button and OOF works fine. Any ideas? Thanks

So it is nothing about web-based services. Is there a firewall? Any record in GC server's Application event log? I would still you collect network trace log for analysis. Fiona Liao TechNet Community Support

Any ideas? No one is experiencing this behavior?