Applies to: Exchange Server 2010 SP3, Exchange Server 2010 SP2

Topic Last Modified: 2012-07-23

You can use the EMC and the Shell to set the connection limits on a computer running Microsoft Exchange Server 2010 that has the IMAP4 service enabled.

When you specify connection limits for IMAP4, you can select connection limits for the server, IP address, or a specific user.

The following table describes the three settings for connection limits.

Descriptions of commands for setting connection limits for IMAP4

Command Description Default value Limits

MaxConnections

Specifies the total number of connections the specified server will accept. This includes authenticated and unauthenticated connections.

2,000

1-25,000

MaxConnectionsFromSingleIP

Specifies the number of connections that the server will accept from a single IP address.

2000

1-25,0000

MaxConnectionsPerUser

Specifies the maximum number of connections that the server will accept from a particular user.

16

1-25,000

Looking for other management tasks related to setting up POP3 and IMAP4? Check out Managing POP3 and IMAP4.

Note:
After you set connection limits, you must restart the IMAP4 service. For information about how to restart the IMAP4 service, see Start and Stop the IMAP4 Service.

Use the EMC to set IMAP4 connection limits for a server, an IP address, or a user

You need to be assigned permissions before you can perform this procedure. To see what permissions you need, see the "POP3 and IMAP4" entry in the Client Access Permissions topic.

  1. In the console tree, navigate to Server Configuration > Client Access.

  2. In the work pane, click the POP3 and IMAP4 tab.

  3. Select IMAP4 and then, in the action pane, under IMAP4, click Properties.

  4. On the IMAP4 Properties page, click the Connection tab.

  5. Under Connection Limits, specify the following:

    • To set the connection limit for a server, enter a value between 1 and 25,000 in the box next to Maximum connections.

    • To set the connection limit for an IP address, enter a value between 1 and 25,000 in the box next to Maximum connections from a single IP address.

    • To set the connection limit for a single user, enter a value between 1 and 25,000 in the box next to Maximum connections from a single user.

  6. Click Apply, and then click OK to save your changes.

Use the Shell to set IMAP4 connection limits for a server, an IP address, or a user

You need to be assigned permissions before you can perform this procedure. To see what permissions you need, see the "POP3 and IMAP4" entry in the Client Access Permissions topic.

This example sets the connection limit for a server.

Copy Code 
Set-ImapSettings -Identity CAS01 -MaxConnections Value

This example sets the connection limit for an IP address.

Copy Code 
Set-ImapSettings -Identity CAS01 -MaxConnectionsFromSingleIP Value

This example sets the connection limit for a user.

Copy Code 
Set-ImapSettings -MaxConnectionsPerUser Value

For more information about syntax and parameters, see Set-ImapSettings.

Other Tasks

After you set IMAP4 connection limits for a server, IP address, or a user, you may also want to: