Unable to Move MS Exchange 2003 mailboxes from one server to another Event ID 9175, 9167 & 1008

I'm unable to move exchange mailboxes from one
server to another. I'm getting Event ID 9175, 9167 & 1008
The exchange server is running and my Exchange store are mounted correctly, we ned to move some mailboxes to reuce the load on the exchynage server.
 
 My environment
Win2K3 SP2
MS Exchange 2003 SP2 STD
 
 This is what I get in the event viewer when trying to move a mailbox.
 
 
Event Type: Error
Event Source: MSExchangeAdmin
Event Category: Recover Mailbox
Event ID: 1041
User:  N/A
Computer: SERVER
Description:
Unable to recover mailbox 'Full Name.
Error: The attempt to log on to the Microsoft Exchange Server computer has failed.
 The MAPI provider failed.
Microsoft Exchange Server Information Store
ID no: 8004011d-0512-00000000
For more information, click http://www.microsoft.com/contentredirect.asp.




Event Type: Error
Event Source: MSExchangeAdmin
Event Category: Recover Mailbox  
Event ID: 9167
 User:  N/A
Computer: SERVER
Description:
Unable to get an administrative interface to the mailbox store on server 'SERVER'.
 Error: The attempt to log on to the Microsoft Exchange Server computer has failed.
 The MAPI provider failed.
Microsoft Exchange Server Information Store
ID no: 8004011d-0512-00000000
For more information, click http://www.microsoft.com/contentredirect.asp.


Event Type: Error
Event Source: MSExchangeAdmin
Event Category: MAPI Session  
Event ID: 9175
 User:  N/A
Computer: SERVER
Description:
The MAPI call 'OpenMsgStore' failed with the following error:  
The attempt to log on to the Microsoft Exchange Server computer has failed.
The MAPI provider failed.
Microsoft Exchange Server Information Store
ID no: 8004011d-0512-00000000
For more information, click http://www.microsoft.com/contentredirect.asp.

 
Any Ideas? The only sloution I found online was http://forums.msexchange.org/m_1800398754/mpage_1/key_/tm.htm#1800398754
and that simply does not work for me because my store is mounted! ..