I've just been having similar problems with a purely Exchange2000 to Exchange2000 move of mailboxes. The win2000 event log reported problems with a particular message (it actually gave some useful information for a change!) The offending message had a duff attachment, which once removed allowed the mailbox move to succeed. Don't know if this helps with 5.5 but might point you in the right direction. Another thing to watch out for is storage quotas on individual mailboxes, if a user is over quota the move fails. -----Original Message----- From: Garland Mac Neill [mailto:gmacneil@xxxxxxxxxxxxx] Sent: 11 June 2002 22:55 To: [ExchangeList] Subject: [exchangelist] Help - Move Mailbox Is hosed...!!!! http://www.MSExchange.org/ - Re-Vamped! Hello all, I'm new to the list. I am in the process of migrating from Exchange 5.5 to E2K. I was able to move about 7 mailboxes when I started off then all of a sudden the MAPI client bit the dust. Below is a brief statement of what I've tracked down so far. If you have any questions please feel free to ask. What am I missing here? The information store starts ok and the mailbox storage mounts fine, which is what Technet suggests. I also get Event ID 9167 and 1008 with the same error. Replication seems to be fine. I've removed the AV s/w. IS this installation hosed? Thanks in advance, Garland Event Type: Error Event Source: MSExchangeAdmin Event Category: MAPI Session Event ID: 9175 Date: 6/11/2002 Time: 10:04:11 AM User: N/A Computer: SAKIC 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 Garland Mac Neill Systems Administrator Solbourne <mailto:gmacneill@xxxxxxxxxxxxx> gmacneill@xxxxxxxxxxxxx ------------------------------------------------------ You are currently subscribed to this MSExchange.org Discussion List as: m.dewell@xxxxxxxxx To unsubscribe send a blank email to $subst('Email.Unsub')