Setting Recipient Limits
Applies To: Windows Server 2003, Windows Server 2003 R2, Windows Server 2003 with SP1
You can determine the maximum number of recipients for a single message sent in one connection. The default is 100, which is the minimum number specified in Request for Comment (RFC) 821. Many clients return messages with a non-delivery report (NDR) after an error message is received, indicating that the maximum number of recipients has been exceeded. The SMTP service does not return messages in this instance. It opens a new connection immediately and processes the remaining recipients. For example, if the recipient limit is set to 100 and a message with 105 recipients is received, the first 100 are delivered in one connection. Then, a new connection is opened, and the message is processed for the remaining five recipients.
Important
You must be a member of the Administrators group on the local computer to perform the following procedure or procedures. As a security best practice, log on to your computer by using an account that is not in the Administrators group, and then use the runas command to run IIS Manager as an administrator. At a command prompt, type runas /User:Administrative_AccountName "mmc systemroot\system32\inetsrv\iis.msc".
Procedures
To set recipient limits
In IIS Manager, right-click the SMTP virtual server, and then click Properties.
Click the Messages tab, select the Limit number of recipients per message to check box, and then type a number to represent the recipient limit. To impose no limit, clear the check box.
Related Information
For information about setting message size limits, see Setting Message Size Limits.
For information about limiting the number of messages per connection, see Limiting the Number of Messages per Connection.
For information about storing non-delivery reports, see Storing Non-Delivery Reports.