Office 2007 Pro on windows xp for clients. Server 2003 R2 x64 SP2 and exchange 2007 build 08.01.0436.000 We only use outlook 2007, so I am not aware if any other versions of outlook have this problem. After Applying KB241217 when loading outlook, it will display "online with microsoft exchange" and give you a windows logon box, but new e-mails will be loaded. If you ignore this prompt (esc), it will work happily for a while and then give it you again. Hitting F9 (send/recieve) gives a little more info as to where it stops for authentication - "Syncronizing Hierarchy". If valid credentials are provided, it will hang indefinatly at "Ofline address book Connecting to Microsoft Exchange". I performed a Test E-mail Autocofiguration using autodiscover, and browsed to https://server.domain/oab/guid/oab.xml (as found from the autoconfiguration test) which worked as far as I could see. When removing the update, the prompt disapears. I've checked NTFS permissions on the OAB folder which had authenticated users with read access. Am I right in thinking this is a OAB problem? What do I need to try next?

Please try to use my suggestions in this thread to check your OAB configuration As the issue only happens when you applied KB241217, I don’t think that the root cause is on the OABPlease remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.

I have checked the permissions and I don't have IIS_IUSERS (But in IIS integrated windows authentication is on), bearing in mind it's exchange 2007, the following don't exist: · Organization Management: Read, special permissions · View-Only Organization Management: Read, special permissions · Exchange Trusted Subsystem: Read However I do have "Exchange organisation administrators" which is set to read, I've also added Exchange View-only Administrators (read) ExBPA healthcheck gives only one critical: Certificate SAN Mismatch (which I'm assmuing comes from the wildcard) (SAN) of SSL certificate for HTTPS://tmail.Domain.com/RPC does not appear to match the host address. Host address: tmail.domain.com. Current SAN: DNS Name=*.domain.com From experience, this is normaly where permission errors are given.

Ravey, Can you check the number on the KB you have listed? 241217 is not a hotfix or patch but a document that references Microsoft Visual C++ version 6.0 http://support.microsoft.com/default.aspx?scid=kb;EN-US;241217 Thanks Nick

Sorry Nic, the correct KB is 2412171 http://support.microsoft.com/kb/2412171 Thanks Dave

Ravey Davey, It may be the version of 2412171 that was installed. Check the following: 2485531 Microsoft Outlook 2007 may experience Send/Receive or performance issues after a recent update has been installed on the computer http://support.microsoft.com/default.aspx?scid=kb;en-US;2485531 Thanks Nick