MSExchangeTransport 1031

 

This article provides an explanation and possible resolutions for a specific Exchange event. If you don't find what you’re looking for here, try searching Exchange 2010 Help.

Details

Product Name

Exchange

Product Version

14.0

Event ID

1031

Event Source

MSExchangeTransport

Category

SmtpReceive

Symbolic Name

SmtpReceiveMessageRateLimitExceeded

Message Text

The connection for user [%1] with IP address [%2] is being dropped. The rate of message submissions from this connection has exceeded the throttling policy of %3 per minute.

Explanation

This Error event indicates that the Exchange Transport service SMTP Receive component rejected an SMTP message that was submitted for delivery.

The Microsoft Exchange Transport service controls the sending and receiving of messages in Microsoft Exchange Server 2010. The Exchange 2010 transport pipeline uses the SMTP Receive component to validate the message content before the message can be submitted to the Submission queue. The SMTP Receive component applies a series of receive events and, if configured, antivirus and anti-spam events to validate the message. Additionally, the SMTP Receive component enforces message throttling policies for users.

Microsoft Exchange Server 2010 includes a new feature that is known as throttling. This feature is a framework to which other Exchange 2010 Client Access server (CAS) components can connect to limit usage of the server's resources. These components include the following:

  • Outlook Web App (OWA)

  • Exchange ActiveSync (EAS)

  • Exchange Web Services (EWS)

  • IMAP4

  • POP3

  • PowerShell

The throttling framework creates a limits-based system that tracks user actions and drops user requests that exceed specified limits. Additionally, the framework provides a way to slow user requests when the CPU usage for a particular CAS component reaches a certain level.

Exchange 2010 throttling may be used to control user access to the following areas:

  • The number of concurrent open connections

  • The time spent connected to a CAS server

  • The time spent performing Active Directory lookup operations and making calls to Active Directory

  • The time spent performing RPC calls to mailbox servers

  • The number of e-mail messages that may be sent

To configure throttling, a group of settings is configured to control how many Exchange resources in the organization are available to a user. This group of settings is known as a throttling policy.

Note   Throttling policies can be used to control only users who connect to Exchange 2010 servers. The policies do not apply to earlier versions of Exchange.

Each setting in a throttling policy has a value. The value represents the amount of access that is given to a user or to an application for the particular setting. This value is known as the budget.

Note   Throttled messages remain in the user's Outbox folder until the throttling policy allows the messages to be sent.

For more information, see the following topics:

User Action

To troubleshoot this issue, determine whether any of the following conditions exist:

  • A program on the user's computer is configured incorrectly. Or, an issue causes the program to try to make too many connections to Exchange or prevents it from disconnecting from Exchange.

  • The user's computer is running a malicious program.

  • An existing throttling policy is not appropriate for the particular user's requirements.

One or more budget settings in the throttling policy may be set too low to provide the user or the program enough time to complete a required task.

Time settings in a policy are specified as a percentage of one minute. Therefore, a time setting of 100 percent represents 60 seconds. For example, Microsoft Outlook Web App settings in a throttling policy control how long a user can run OWA code against a CAS server and also how long the user can connect to the CAS server. As an example, you may have the following settings configured:

  • OWAPercentTimeInCAS 1

  • OWAPercentTimeInMailboxRPC 1

In this example, the policy settings have a value of 1. This represents one percent of one minute for each setting. Exchange calculates one percent of one minute as 600 milliseconds. Therefore, in this example, the user who is logged on to OWA can access Exchange for up to 600 milliseconds. After this time, the connection becomes over-budget. Exchange 2010 does not allow further access until one minute after the 600 millisecond budget is reached. After this time, the user can again access OWA for 600 milliseconds.

To manage throttling policies in Exchange 2010, use the following cmdlets:

  • Get-ThrottlingPolicy

  • New-ThrottlingPolicy

  • Set-ThrottlingPolicy

  • Remove-ThrottlingPolicy

For more information, see Understanding Client Throttling Policies.