Hi there Exchange experts!I have a bigproblem with reinstalling Exchange 2007.2 days ago I uninstalled Exchange because I had to rename the servers. I have 2 Exchange servers in a domain. On number 1 I re-installed the mailbox role succesfully. On the other i tried to reinstall the hub and the client access role. But whatever I try, I keep getting the following error message every time:"Error message when you try to reinstall Exchange 2007: "Could not find the default Administrative Group 'Exchange Administrative Group (FYDIBOHF23SPDLT)""Now there's an Microosft knowledgebase article about this:http://support.microsoft.com/kb/937358But this advise doesn't work. I removed the 'watermark' entry in the registry but then when trying to reinstall, the registry entry returns! I cannot find any other possible solutions on the internet. i checked DNS and everything is correct. Also AD replication is working succesfully.I hope someone can help me out! Thanks in advance!!Best regards,Vincent

HiTry to run the /PrepareAD command again.Regards Syed Arsalan .syed.arsalan

Hi Agreed with sysed. /prepareAD switch should create Exchange Administrative group.Regards Chinthaka Shameera | MCITP: EA | MCSE: M | http://howtoexchange.wordpress.com/

In keeping with others comments, you need to prep the AD again to add the missing Administrative Group - the kb you actually link to also mentions this, you will need to be an Enterprise Admin.The Schema will be fine so you don't need to prep.Oliver

I agree with others you need to run /prepareAD in order to recover your container See below are tasks performed by /prepareAD If the MicrosoftExchange container does not exist, this command creates it under CN=Services,CN=Configuration,DC=<rootdomain >. Verifies that the schema has been updated and that the organization is up to date by checking the objectVersion property in Active Directory. The objectVersion property is in the CN= <your organization> , CN=Microsoft Exchange,CN=Services,CN=Configuration,DC= <domain> container. The objectVersion value for the release to manufacturing (RTM) version of Exchange 2007 is 10666. Creates the following universal security groups (USGs) within the MicrosoftExchange Security Groups OU: Exchange Organization Administrators Exchange Recipient Administrators Exchange Servers Exchange View-Only Administrators Exchange Public Folder Administrators (New in ExchangeServer2007ServicePack1) ExchangeLegacyInterop Adds the new USGs that are within the MicrosoftExchange Security Groups OU to the otherWellKnownObjects attribute that is stored on the CN=MicrosoftExchange,CN=Services,CN=Configuration,DC=<rootdomain > container. This command creates the Exchange2007Administrative Group called ExchangeAdministrative Group (FYDIBOHF23SPDLT). It also creates the Exchange2007Routing Group called ExchangeRouting Group (DWBGZMFD01QNBJR). Refer Below http://technet.microsoft.com/en-us/library/bb125224.aspx Vinod |CCNA|MCSE 2003 +Messaging|MCTS|ITIL V3|