During exchange mailbox or calendar migration an error similiar to below may be encountered:
System.Collections.Generic.KeyNotFoundException: The given key was not present in the dictionary.
at System.Collections.Generic.Dictionary`2.get_Item(TKey key)
at Dell.MigrationManagerForExchange.General.Ews.Autodiscover.GetEwsUrl(String emailAddress, NetworkCredential creds, Uri& autodiscoverUrl, Boolean enableScpLookup)
at Dell.MigrationManagerForExchange.General.Ews.EwsSessionCreator.DiscoverUrl()
at Dell.MigrationManagerForExchange.General.Ews.EwsSessionCreator.get_Url()
at Dell.MigrationManagerForExchange.General.Ews.EwsSessionCreator.GetExchangeService()
at Quest.MigrationManager.Exchange.MigrationConnectors.EwsSyncConnector.get_Exs()
at Quest.MigrationManager.Exchange.MigrationConnectors.EwsSyncConnector.ConnectInternal()
at Quest.MigrationManager.Exchange.MigrationConnectors.EwsSyncConnector.ReconnectOverAutodiscover()
at Quest.MigrationManager.Exchange.MigrationConnectors.EwsSyncConnector.Connect()
at Quest.MigrationManager.Exchange.Agent.Jobs.DisPlusO365JobBase.ConnectOverEws()
at Quest.MigrationManager.Exchange.Agent.Jobs.DisBaseJob.ConnectionOverEws()
at Quest.MigrationManager.Exchange.Agent.Jobs.DisBaseJob.PerformSync()
at Quest.MigrationManager.Exchange.Agent.Jobs.DisBaseJob.RunJob()