What is message waiting indicator
Troubleshooting the Messaging Waiting Indicator status in Exchange 2010 Unified Messaging server
There are a number of ways an end-user may learn that they have new voice mail, such as from client software like Microsoft Outlook, OWA. Lync, Communicator, or different types of indicators on IP. smart and traditional phones. The term Message Waiting Indicator (MWI) is usually applied to notifications delivered by the user’s phone using mechanisms such as a light on the phone, a special icon or highlighted notification or even a special dial tone. Exchange 2010 includes built-in support for MWI .
Exchange 2010 Unified Messaging also includes a feature called Voice Mail Preview which uses automatic speech recognition (ASR) to add a text version of the voice mail that's delivered to the user's Inbox (along with the MP3 voice message). This allows users to read their voicemail messages. See Voice Mail Preview Advisor for Exchange 2010 for details.
This article describes steps on how to use the event logs on Exchange 2010 Unified Messaging (UM) and Mailbox servers to troubleshoot MWI failures. Also included in this article are settings to validate MWI configuration on Exchange.
Flow of MWI notifications on Exchange servers
- A voice message is left for a user and is stored in the user's Exchange mailbox on a Mailbox server.
- The Mailbox Assistant service on the Mailbox server checks the status of voice mails in the user’s mailbox.
- The Mailbox Assistant service makes an RPC connection to a Unified Messaging server associated
with the user’s UM Dial Plan.
- The UM server sends a SIP NOTIFY message with the MWI state change to a UM IP Gateway associated with the user’s UM Dial Plan.
Check the event log on the mailbox server
Confirming the Mailbox server is not logging MWI errors will help to isolate the problem to a later notification handling step. The first step in sending the MWI notification is the retrieval of the MWI state from the user’s mailbox on the mailbox database. Once the state of the MWI is known, the mailbox server must be able to make an RPC connection with the UM server to relay the MWI state information. Any of the following events, if found on the Mailbox server, would be the starting point for a deeper look at the Mailbox server. Also UM event logging can be increased on the mailbox server to confirm that the MWI notification was successfully sent to the UM server.
On the Exchange 2010 Mailbox server, look for Event ID 1346 in the Application Event log. It indicates there may be an issue with the database or the database might be dismounted.
Task Category: MWI General
Presence of Event ID 1345 on the Mailbox server indicates there may be a problem with the user’s mailbox. The ‘Additional information’ will contain MAPI error codes and additional information to diagnose the specific issue. Here's an example:Source: blogs.technet.com