URGENT: Cant connect to Exchange 2010 after SP2 broken upgrade

I tried to install the SP2 for Exchange 2010 ( SP1 was installed )

after the prerequesit checks went through the upgrade stopped all of a sudden with the following error message:

[08.15.2012 19:16:20.0962] [2] Beginning processing Set-WERRegistryMarkers
[08.15.2012 19:19:21.0080] [2] [ERROR] Provisioning layer initialization failed: 'Failed to reconnect to Active Directory server dc01.lan. Make sure the server is available, and that you have used the correct credentials.'
[08.15.2012 19:19:21.0080] [2] [ERROR] Failed to reconnect to Active Directory server dc01.lan. Make sure the server is available, and that you have used the correct credentials.
[08.15.2012 19:19:21.0080] [2] [ERROR] Active Directory server dc01.lan is not available. Please retry at a later time.
[08.15.2012 19:19:21.0095] [1] The following 1 error(s) occurred during task execution:
[08.15.2012 19:19:21.0095] [1] 0.  ErrorRecord: Provisioning layer initialization failed: 'Failed to reconnect to Active Directory server dc01.lan. Make sure the server is available, and that you have used the correct credentials.'
[08.15.2012 19:19:21.0095] [1] 0.  ErrorRecord: Microsoft.Exchange.Provisioning.ProvisioningBrokerException: Provisioning layer initialization failed: 'Failed to reconnect to Active Directory server dc01.lan. Make sure the server is available, and that you have used the correct credentials.' ---> Microsoft.Exchange.Data.Directory.ADTransientException: Failed to reconnect to Active Directory server dc01.lan. Make sure the server is available, and that you have used the correct credentials. ---> System.DirectoryServices.ActiveDirectory.ActiveDirectoryServerDownException: Active Directory server dc01.lan is not available. Please retry at a later time.
   --- End of inner exception stack trace ---
   at Microsoft.Exchange.Data.Directory.ConnectionPoolManager.GetConnectionFromPool(ConnectionPoolType connectionPoolType, ADObjectId domain, String serverName, Int32 port, Boolean& serverConnectionPresentButDownOrDisconnected)
   at Microsoft.Exchange.Data.Directory.ConnectionPoolManager.GetConnection(ConnectionType connectionType, ADObjectId domain, String serverName, Int32 port, NetworkCredential credential)
   at Microsoft.Exchange.Data.Directory.ConnectionPoolManager.GetConnection(ConnectionType connectionType, NetworkCredential networkCredential, String serverName, Int32 port)
   at Microsoft.Exchange.Data.Directory.ADSession.GetConnection(String preferredServer, Boolean isWriteOperation, Boolean isNotifyOperation, String optionalBaseDN, ADObjectId& rootId, ADScope scope)
   at Microsoft.Exchange.Data.Directory.ADSession.GetReadConnection(String preferredServer, ADObjectId& rootId, ADRawEntry scopeDeteriminingObject)
   at Microsoft.Exchange.Data.Directory.ADGenericReader.GetNextResultCollection(Type controlType, DirectoryControl& responseControl)
   at Microsoft.Exchange.Data.Directory.ADPagedReader`1.GetNextResultCollection()
   at Microsoft.Exchange.Data.Directory.ADGenericPagedReader`1.GetNextPage()
   at Microsoft.Exchange.Data.Directory.ADGenericPagedReader`1.<GetEnumerator>d__4.MoveNext()
   at Microsoft.Exchange.Data.Directory.SystemConfiguration.ADSystemConfigurationSession.FindCmdletExtensionAgents(Boolean enabledOnly, Boolean sortByPriority)
   at Microsoft.Exchange.Provisioning.ProvisioningBroker.ctor()
   --- End of inner exception stack trace ---
   at Microsoft.Exchange.Provisioning.ProvisioningBroker.ctor()

Select allOpen in new window