Manual switch or unswitch of an O365 mailbox causes the following error to occur in the MMEX console:
"Failed to (Un)Switch user. Interface not registered (Exception from HRESULT: 0x80040155)"
Additionally the console log (EMWMigration.log) will contain the following error:
Error System.Runtime.InteropServices.COMException (0x80040155): Interface not registered (Exception from HRESULT: 0x80040155)
at DirectoryMigration.DMProjectClass.get_Objects()
at Dell.MigrationManagerForExchange.Shared.Switching.O365SwitcherAndMatcher.FindPair(String sourceGuid)
at Dell.MigrationManagerForExchange.Shared.Switching.O365SwitcherAndMatcher.Unswitch(Guid sourceGuid)
at Quest.MigrationManager.Exchange.O365ProvisioningWebService.O365ProvisioningProxy.<>c__DisplayClassa.<Unswitch>b__9()
at Quest.MigrationManager.Exchange.O365ProvisioningWebService.O365ProvisioningProxy.InvokeTryCatchAction(Action act) at Quest.MigrationManager.Exchange.O365UserProvisioning.O365UserProvisioning.CheckAndThrow(Func`1 exceptionFunc)
at Quest.MigrationManager.Exchange.O365UserProvisioning.O365UserProvisioning.Unswitch(Int32 mailboxId, Int32 collectionId, Boolean rollbackUnswitchOnFail)