Notice: This website is an unofficial Microsoft Knowledge Base (hereinafter KB) archive and is intended to provide a reliable access to deleted content from Microsoft KB. All KB articles are owned by Microsoft Corporation. Read full disclaimer for more details.

Maximum number of rules per folder in the Inbox or in a public folder in Exchange Server 2003, Exchange 2000, and Exchange Server 5.5

View products that this article applies to.


Microsoft Exchange Server can define rules to automatically operate on messages in the Inbox or in a public folder. There is a 32-kilobyte (KB) "packed data" memory limit for the rules on each folder in the Inbox or in a public folder. The reason for the memory limit is that the total sum of the information that is contained in a user's rules must fit in a remote procedure call (RPC).

Sometimes, you may receive the following error message when the number of rules exhausts the 32-KB memory limit:
changes to the rule could not be saved. There is not enough memory or the rules are too complex. Try deleting some rules.

↑ Back to the top

More information

The maximum number of rules depends on the size of the rules that are defined. Additionally, the amount of data that is required for a rule varies depending on the rule.

For example, a rule to move messages into a folder for a single recipient takes about 660 bytes. Therefore, there is no defined limit for the maximum number of rules that can be assigned to a folder. Typically, the limit is between 40 and 50 rules per folder.

For more information about the maximum number of rules per folder in the Inbox or in a public folder in Microsoft Exchange Server 2007, visit the following Microsoft Web site:

↑ Back to the top

Keywords: KB147298, kbenv

↑ Back to the top

Article Info
Article ID : 147298
Revision : 4
Created on : 10/29/2007
Published on : 10/29/2007
Exists online : False
Views : 370