I have recently lost the ability to migrate mailboxes from Exchange 2003 servers to Exchange 2007 servers. From the EMC I select the legacy mailbox, right click, select move mailbox, select the Exch 2007 store, move and get the following message:Error occurred in the step: Opening source mailbox. Failed to open mailbox with error: An unknown error has occurred., error code: -1056749262i also get the Event ID: 1008 in the app log.Using the same account I can move a mailbox from Exch 2003 to 2003 and Exch 2007 to Exch 2007 but not from 2003 to 2007. I recently migrated serveral hundred mailboxes from 2003 to 2007 and now looking to clean up some service accounts so I can decommision 2003. But now i get an error. Single domain forest, we have 2003 and 2008 DCs.On the Exch 2007 i have run the at the request of MS support: Setup \PSetup \PD setup \preparelegacyexchangepermissionsbut still i can't move any mailboxes from 2003 -> 2007Jcon

Hi,Which permissions does the account have on the mailboxes. Maybe the permissions differ between the already migrated boxes and the other ones? Regards,JohanExchange-blog: www.johanveldhuis.nl

Hi,Performing the below steps should resolve the issue.1. Open ESM on the 2003 Server. 2. Drill down through Administrative Groups->first administrative group->Servers-> <<your server>> 3. Right-click on your server and go to Properties. Select the Security tab. 3. Click Advanced, then check the box at the bottom for "Allow inheritable permissions..." also Check if you have the the registry key Disable MAPI Clients set at the below locationHKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MSExchangeIS\ParametersSystemIf yes please go ahead and remove the same and than try move the mailbox.Mahendra

2003 full admin rights2007 server admin, recipient admin, view only admin, and org admin.Jcon

Exchange server has Allow inheritable permissions checked. Reg key does not exist.Jcon

Did you check that the inheritable permissions option is checked on all the stores on that server?Mahendra

Hi,Whether only one mailbox could not be moved?Please run EXBPA on the Exchange 2003 to check the relevant inheritable permissions.ThanksAllen

Can you make sure these accounts are not set to hide from the global address listFull time IT consultant since 1998 mainly on Exchange\ISA\AD MCSE NT4.0,2000/2003, CCNA MCITP: Enterprise Messaging Administrator 2007/2010 MCT since 2001

The 2003 servers are Standard edition therefore they only have 1 store. I have verified the stores on the 2003 servers are set to inherit permissions. I also found that there is a Deny on the server level setup for "receive as" for (domain\Exchange Servers) and (domain\Exchange Domain Servers). It is inherited from the parent object. I have checked the server, and the org. I am not sure where this is coming from.Jcon

I ran the EXBPA on the 2003 servers, I did not see any errors that came back on the permission scan.Jcon

I verified the accounts are not hidden from the GAL.Jcon

This issue was permission based. I resolved it with the following steps:1. Removed the inheritance to the Exchange 2003 server in ESM but copied the permissions. Applied.2. Readded the inheritance3. gave the admin account full control rights at the server level in ESM.At that time I could migrate mailboxes to Exchange 2007 again.I am not sure why this worked and I feel that this is a work around more than a solution. I will be decommisioning the 2003 servers at the end of the month.Jcon