Microsoft Exchange Performance Counters

Microsoft Exchange Unified Messaging System Availability counters

There are many performance counters that can be used to maintain and troubleshoot a computer that's running Microsoft Exchange Server 2010. Unified Messaging performance counters are used to measure quantities of information or data for Unified Messaging based on the number, size, duration, and rate of data that's being requested or received. Object: MSExchangeAvailability

Counter Name	Description
% of Failed Mailbox Connection Attempts Over the Last One Hour
% of Inbound Calls Rejected by the UM Service over the Last Hour	% of Inbound Calls Rejected by the UM Service Over the Last Hour is the percentage of incoming calls that were rejected by the Microsoft Exchange Unified Messaging service in the last hour.
% of Inbound Calls Rejected by the UM Worker Process Over the Last Hour	% of Inbound Calls Rejected by the UM Worker Process Over the Last Hour is the percentage of incoming calls that were rejected by the UM Worker process in the last hour.
% of Messages Successfully Processed Over the Last Hour	% of Messages Successfully Processed Over the Last Hour is the percentage of messages that were successfully processed by the Microsoft Exchange Unified Messaging service in the last hour.
% of Partner Voice Message Transcription Failures Over the Last Hour	% of Partner Voice Message Transcription Failures Over the Last Hour is the percentage of partner voice message transcription failures in the last hour.
Call Answer Queued Messages	Call Answer Queued Messages is the number of messages created and not yet submitted for delivery.
Calls Disconnected by UM on Irrecoverable External Error	Calls Disconnected by UM on Irrecoverable External Error is the number of calls disconnected after an irrecoverable external error occurred.
Calls Disconnected by UM on Irrecoverable External Error/sec	Calls Disconnected by UM on Irrecoverable External Error/sec is the number of calls disconnected after an irrecoverable external error occurred in the last second
Calls Disconnected on Irrecoverable Internal Error	Calls Disconnected on Irrecoverable Internal Error is the number of calls that were disconnected after an internal system error occurred.
Directory Access Failures	Directory Access Failures is the number of times that attempts to access Active Directory failed.
Failed Mailbox Connection Attempts %	Failed Mailbox Connection Attempts % is the percentage of failed attempts to connect to the Mailbox server.
Incomplete Signaling Information	Incomplete Signaling Information is the number of calls for which the signaling information was missing or incomplete.
Maximum Calls Allowed	Maximum Calls Allowed is the length of time, in seconds, that the server concurrently processed the maximum number of calls allowed.
Name TTSed	Name TTSed is the number of times the system used Text-to-Speech (TTS) to create an audio version of the display name of a subscriber.
Queued OCS User Event Notifications	Queued OCS User Event Notifications is the number of notifications that have been created and not yet submitted for delivery.
Spoken Name Accessed	Spoken Name Accessed is the number of times the system retrieved the recorded name of a user.
Total Worker Process Call Count	Total Worker Process Call Count is the number of calls handled by this UM worker process.
Worker Process Recycled	Worker Process Recycled is the number of times a new UM worker process has been started.