When running update on Exchange 2007 OAB, the following error is reported: Action 'Update' could not be performed on object 'Default Offline Address List'. Default Offline Address ListFailedError:Failed to generate the content of the offline address book '\Default Offline Address List'. Two possible reasons for the failure are that the System Attendant Service is not running or you do not have permission to perform this operation. Error message : 'Catastrophic failure (Exception from HRESULT: 0x8000FFFF (E_UNEXPECTED))'. Catastrophic failure (Exception from HRESULT: 0x8000FFFF (E_UNEXPECTED)) Autodiscover configured as per: http://technet.microsoft.com/en-us/library/bb201695.aspx Checked: Organizational Configuration - Mailbox - Offline Addresslist Click Properties - Distribution Verify thatCAS servers are listed in Enable web based distribution Web based distro is grayed out - can't select. CAS is on the same server as Exchange. No errors in Event log. Run Test-OutlookWebServices And receive Test-OutlookWebServices Id Type Message -- ---- ------- 1003 Information About to test AutoDisc... 1007 Information Testing server svr-dc0... 1019 Information Found a valid AutoDisc... 1006 Information The Autodiscover servi... 1016 Success [EXCH]-Successfully co... 1015 Information [EXCH]-The OAB is not ... 1014 Success [EXCH]-Successfully co... 1016 Information [EXPR]-The AS is not c... 1015 Information [EXPR]-The OAB is not ... 1014 Information [EXPR]-The UM is not c... 1017 Success [EXPR]-Successfully co... 1006 Success The Autodiscover servi... Need to know how to expand Shell output so I can see the entire messages above. Domain used to have an Exchange 2003 server. All users, public folders and address books were migrated. All commands were run to update the address lists. Thanks ahead for any input.

I went through the same process many months ago, and I'll try to remember exactly what I did to fix it. I had also migrated from 2003 and was receiving the exact error messages that you are.I had 2 servers, one acting as a CAS and the other as MB and HT.I think I started with creating a service record locator in my local DNS for autodiscover. Check this link for info:http://support.microsoft.com/kb/940881At this point, I believe I deleted the Offline Address Book completely and rebooted both servers, CAS then MB/HT.I then created a new Default Offline Address Book in Org Configuration-Mailbox-Offline Address Book.In Server Configuration-Mailbox-Mailbox Database-Client Settings, I made sure that it was associated with the new OAB that I had just created.After this, things started working again and I didn't receive the errors.I know it seems drastic to delete the default OAB but it was the only thing I was able to do to fix it, after many days of troubleshooting.