The DNS server was unable to open Active Directory

I have two DC's: DCA and DCB.
Problem is also that DCA has a problem with DNS, somehow I can't create new zones in the AD. And DCA can't access DCB for example. DCA has all FMSO roles but DCB doesn't see that. On DCA (both are also Exchange Server, intention is to move Exchange IS to DCB and demote and remove DCA) Exchange services won't start. Some errors from the eventlog:

Event Type:     Error
Event Source:     Userenv
Event Category:     None
Event ID:     1053
Date:          1/23/2006
Time:          9:59:43 AM
User:          NT AUTHORITY\SYSTEM
Computer:     DCA
Description:
Windows cannot determine the user or computer name. (Access is denied. ). Group Policy processing aborted.

For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.

Event Type:     Error
Event Source:     Userenv
Event Category:     None
Event ID:     1030
Date:          1/23/2006
Time:          9:59:27 AM
User:          DOMAIN\Administrator
Computer:     DCA
Description:
Windows cannot query for the list of Group Policy objects. Check the event log for possible messages previously logged by the policy engine that describes the reason for this.

For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.

Event Type:     Error
Event Source:     MSExchangeDSAccess
Event Category:     Topology
Event ID:     2114
Date:          1/23/2006
Time:          9:58:30 AM
User:          N/A
Computer:     DCA
Description:
Process INETINFO.EXE (PID=428). Topology Discovery failed, error 0x80040931.

For more information, click http://www.microsoft.com/contentredirect.asp.

Event Type:     Warning
Event Source:     LSASRV
Event Category:     SPNEGO (Negotiator)
Event ID:     40960
Date:          1/23/2006
Time:          10:01:37 AM
User:          N/A
Computer:     DCA
Description:
The Security System detected an authentication error for the server ldap/dca.DOMAIN.LOCAL/DOMAIN.LOCAL@DOMAIN.LOCAL.  The failure code from authentication protocol Kerberos was "The attempted logon is invalid. This is either due to a bad username or authentication information.
 (0xc000006d)".

For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.
Data:
0000: 6d 00 00 c0               m..À    


Event Type:     Warning
Event Source:     LSASRV
Event Category:     SPNEGO (Negotiator)
Event ID:     40960
Date:          1/23/2006
Time:          10:00:09 AM
User:          N/A
Computer:     DCA
Description:
The Security System detected an authentication error for the server DNS/dcb.domain.local.  The failure code from authentication protocol Kerberos was "The attempted logon is invalid. This is either due to a bad username or authentication information.
 (0xc000006d)".

For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.
Data:
0000: 6d 00 00 c0               m..À    


Event Type:     Error
Event Source:     Kerberos
Event Category:     None
Event ID:     4
Date:          1/23/2006
Time:          9:11:13 AM
User:          N/A
Computer:     DCA
Description:
The kerberos client received a KRB_AP_ERR_MODIFIED error from the server host/dca.domain.local.  The target name used was ldap/dca.DOMAIN.LOCAL/DOMAIN.LOCAL@DOMAIN.LOCAL. This indicates that the password used to encrypt the kerberos service ticket is different than that on the target server. Commonly, this is due to identically named  machine accounts in the target realm (DOMAIN.LOCAL), and the client realm.   Please contact your system administrator.

For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.

 

Reinstalled DNS on DCA but see the following error in the Event Log:

Event Type:     Error
Event Source:     DNS
Event Category:     None
Event ID:     4000
Date:          1/23/2006
Time:          10:59:25 AM
User:          N/A
Computer:     DCA
Description:
The DNS server was unable to open Active Directory.  This DNS server is configured to obtain and use information from the directory for this zone and is unable to load the zone without it.  Check that the Active Directory is functioning properly and reload the zone. The event data is the error code.

For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.
Data:
0000: 2d 23 00 00               -#..    


When I try to install the DNS (the AD zones) the following messages appear:

The forward lookup zone cannot be added to the server
The specified directory partition does not exist.

Hope that someone can help me with this problem....