Windows 2012 has two categories of event logs: Windows logs which includes the usual Application, Security and System event logs, and Applications and Services . Applications and Services logs are a new category of event logs that are used to store events from a single application or component, such as Exchange. This new category of event logs is referred to as an application's crimson channel. Exchange 2013 makes use of this and logs events to crimson channels in the Applications and Services logs area. To view these channels: Open Event Viewer; I n the console tree, navigate to Applications and Services Logs -> Microsoft -> Exchange; Under Exchange, select the crimson channel HighAvailability or MailboxDatabaseFailureItems . The HighAvailability channel contains events related to startup and shutdown of the Microsoft Exchange Replication service and other components that run within it, such as Active Manager or VSS writer for example. The HighAvailabili