Exchange 2007 SP1 Rollup 8 is available. You can download it here.

Update Rollup 8 for Exchange Server 2007 SP1 fixes the issues that are described in the following Microsoft Knowledge Base articles:

• 948856  Event ID 9667 occurs when you create a new named property on an Exchange Server 2007 server
• 952935  A software update is available that provides the log tracing feature for the LogTruncator tag in Exchange Server 2007
• 954639  Exchange Information Store service stops responding intermittently on an Exchange 2007 server
• 955480  Meeting requests from external senders are displayed as Busy instead of Tentative in an Exchange 2007 environment
• 956633  User calendar permissions are removed after you run the Set-MailboxCalendarSettings cmdlet in an Exchange Server 2007 environment
• 957640  The “test-*” command fails when you run it on a site that contains only CAS roles in an Exchange 2007 environment
• 958239  Exchange Server 2007 does not generate an event log message for public folder replication messages even though a property validation exception is thrown and the replications do not occur
• 958881  All HTML content in attachment files of messages is run through an HTML filter when you open or save the attachment by using Outlook Web Access (OWA)
• 958938  The importance attribute of a message is lost when an Exchange 2007 user accesses a high-importance message or a low-importance message from Exchange Server 2007 by using a non-Outlook POP3 client or IMAP4 client
• 959510  A meeting request that is sent from OWA causes a “553 5.0.0 Message-Id header line format error” NDR message in an Exchange Server 2007 environment
• 959748  An account with the “Exchange View-Only Administrator” permission can review user mailbox contents by using an administrative application in Exchange Server 2007
• 959861  Some clients cannot connect to back-end Exchange Server 2003 IMAP servers after Exchange 2007 Service Pack 1 RU2 is applied
• 959990  An error occurs when you try to update a recurring appointment by using an Outlook client that is connected to an Exchange 2007 server
• 960178  You receive an NDR when you send an e-mail using OWA Premium and the ANR cache if the Exchange organization name has more than one space
• 960354  Edge Attachment Filtering does not honor the ExceptionConnectors value in Exchange Server 2007
• 960367  Error message when you run the Export-Mailbox command on a folder that has more than 5000 items in Exchange 2007: “-1056749164″
• 960495  The Information Store service crashes continuously on an Exchange Server 2007 server
• 960633  The Microsoft Exchange Information Store service crashes on an Exchange Server 2007 that has the mailbox server role installed
• 960703  Extended characters are replaced by question marks when you send an e-mail message that contains extended ASCII characters by using an IMAP4 client in Exchange 2007
• 960775  You receive a “Message too large for this recipient” NDR that has the original message attached after you restrict the Maximum Message Send Size value in Exchange Server 2007
• 960869  A queue that has multiple connections cannot enter a Retry state in Exchange Server 2007
• 961152  The Exchange information store service (Store.exe process) crashes intermittently when you migrate user data from Lotus Notes to Exchange Server 2007
• 961347  Error message when you export an Exchange 2007 mailbox to a .pst file and a filter is defined: “Export-Mailbox : Error was found for <username> (<SMTP address>)”
• 961443  Users cannot use Outlook Web Access for Exchange Server 2007 to open an address book
• 961524  Some journal messages are stuck in the Submission queue in Exchange Server 2007
• 961606  After you apply Rollup Update 5 for Exchange Server 2007 S961606, Outlook Web Access users find the font size of plain text messages is extremely small when they use some third-party Web browsers
• 961693  Japanese (1 byte Kana) characters in the subject and display name are corrupted when you try to reply or forward task requests or calendar items in Outlook client
• 962235  The date and time information for a “Follow Up” flag is missing if an Exchange 2007 user sends a message to an external recipient
• 966535  Duplicate messages are sent to an external recipient if the recipient is included in multiple distribution lists in an Exchange Server 2007 environment
• 967038  Many log entries are generated in Exchange Server 2007 if you turn on the Exchange log to audit the logons that do not use the primary account for shared resource mailboxes
• 967097  Users may receive duplicate calendar items for the updated instance on mobile devices
• 967109  A delegate cannot accept a meeting request for an online meeting in an Exchange Server 2007 environment
• 967255  Only the tracing information of the last user is logged when you configure Exchange Server 2007 to trace multiple users at the same time
• 968310  Many log entries are generated on an Exchange Server 2007 computer when you enable the Exchange log to audit user logons that do not use the primary account for their mailbox
• 968352  The W3wp.exe process crashes when you use the Italian version of the spelling checker on a message in Outlook Web Access in Exchange 2007
• 968589  The managed policy does not work if the ptagProvisionedFid attribute is missing in Exchange Server 2007
• 968673  The EdgeTransport.exe file of Exchange 2007 servers crashes continuously and Event ID 10003 and Event ID 5000 occur
• 968745  Incomplete tasks show in the Complete tasks view in OWA 2007 in an Exchange 2007 environment
• 968966  Many log entries are generated in Exchange Server 2007 if you turn on the Exchange log to audit administrator logons that do not use the primary account for mailboxes
• 969690  Unresolved sender for delivery status notifications after applying update rollup 7 for Exchange Server 2007 Service Pack 1
• 970687  A search operation in Outlook does not return a correct result if there is a corrupted HTML message in the target folder in an Exchange Server 2007 environment

After you’ve installed a new Exchange 2010 environment and you try to delete the first automatically created mailbox database, you’ll receive the following error.

————————————————————————————
The mailbox database ‘DB01′ cannot be deleted.

DB01
Failed
Error:
This mailbox database contains one or more mailboxes or arbitration mailboxes. To get a list of all mailboxes in this database, run the command Get-Mailbox -Database <Database ID>. To get a list of all arbitration mailboxes in this database, run the command Get-Mailbox -Database <Database ID> -Arbitration. To disable a non-arbitration mailbox so that you can delete the mailbox database, run the command Disable-Mailbox <Mailbox ID>. Arbitration mailboxes should be moved to another server; run the command Move-Mailbox <Mailbox ID> -Arbitration -TargetDatabase <Database ID>.  To remove the arbitration mailbox if this is the last server in the organization, run the command Remove-Mailbox <Mailbox ID> -Arbitration -RemoveLastArbitrationMailboxAllowed.
————————————————————————————

You cannot remove the database, because there are some mailboxes in it. Oké….let’s have look what mailboxes are left in this mailbox database.

Get-Mailbox -Database DB01

As you can see, there are no mailboxes left in de mailbox database, but why we are still receiving this error!! This is the answer…….there are two hidden mailboxes left in de mailbox database, called arbitration mailboxes. With the following command you’re able to see this mailboxes

Get-Mailbox -Database DB01 -Arbitration | ft -wrap -auto

When you move these two mailboxes to another mailbox database, all the error messages are gone! So let’s do that!

Move-Mailbox “SystemMailbox{1f05a927-3be2-4fb9-aa03-b59fe3b56f4c}”  -Arbitration -TargetDatabase DB02
Move-Mailbox “SystemMailbox{e0dc1c29-89c3-4034-b678-e6c29d823ed9}”  -Arbitration -TargetDatabase DB02

Exchange 2010 uses a new mechanism for High Availability. Watch this interresting movie from one of the members of the Exchange 2010 team.

 The continuous availability architecture built into Exchange 2010 provides new benefits for organizations and their messaging administrators:

• Multiple server roles can co-exist on servers that provide high availability. This enables small organizations to deploy a two-server configuration provides full redundancy of mailbox data, while also providing redundant Client Access and Hub Transport services.
• An administrator no longer needs to build a failover cluster in order to achieve high availability. Failover clusters are now created by Exchange 2010 in a way that is invisible to the administrator. Unlike previous versions of Exchange clusters which used an Exchange-provided cluster resource DLL named ExRes.dll, Exchange 2010 no longer needs or uses a cluster resource DLL. Exchange 2010 uses only a small portion of the failover cluster components, namely, its heartbeat capabilities and the cluster database, in order to provide database mobility.
• Administrators can add high availability to their Exchange 2010 environment after Exchange has been deployed, without having to uninstall Exchange and then re-deploy in a highly availability configuration.
• Exchange 2010 provides a view of the event stream that combines the events from the operating system with the events from Exchange.
• Because storage group objects no longer exist in Exchange 2010, and because mailbox databases are portable across all Exchange 2010 Mailbox servers, it is very easy to move databases when needed.