I was recently working on migration from Exchange 2010 to Office 365 using DMM 8.11. I have installed DMM AD/Exchange console on computer1 and had a dedicated agent host computer2 to host my Mage agents.
When I tried to execute a manual switch of a mailbox I was getting following error in EMWMigration.log file:
2016-04-18 14:27:38.8865 Px1478 Tx25 A- C- M- Info MAPI logging on to the mailbox : /o=System Exchange Organization/ou=Exchange Administrative Group (FYDIBOHF23SPDLT)/cn=Recipients/cn=Testuser (server : CASserver, user: migration1, connection flags: aeCONNECT_REMOTE_2010)
2016-04-18 14:27:39.5584 Px1478 Tx25 A- C- M- Error Quest.MigrationManager.Exchange.Basis.MapiLogonException: Mapi logon failed. | at Quest.MigrationManager.Exchange.Basis.MAPISessionCreator.CreateSessionAndLogon(String serverName, String mailboxName, String userName, String domainName, String password, CONNECT_FLAGS flags, IMapiStore& primaryStore)
2016-04-18 14:27:42.4491 Px1478 Tx25 A- C- M- Error O365UserProvisioning|Quest.MigrationManager.Exchange.O365UserProvisioning.O365UserProvisioning.Switch\tError: Exception:
Quest.MigrationManager.Exchange.O365UserProvisioning.SwitchException: Failed to Switch user. —> Quest.MigrationManager.Exchange.Basis.MapiLogonException: Mapi logon failed. —> System.Runtime.InteropServices.COMException (0x8004010F): File: ‘aeMAPISession.cpp’ Line: ‘112’
It turned out that to perform manual switch you need to have Mage installed on the same computer as DMM console even if you are not using it for mail synchronization.