Microsoft updated the documentation for Exchange Server Quota Message Service.

The Microsoft Exchange Server Quota Message Service is a tool that enables custom quota messages to be generated without having to modify DLLs or use an event sink. These messages inform users that they have exceeded their message quotas. This document provides information about downloading and installing the tool and then using it. There is also information about registry entries the configure and control Quota Message Service.

The Quota Message Service is supported on the following versions of Exchange Server:

• Exchange Server 2003 Service Pack 1 (SP1) and later versions
• Exchange 2000 Server. Must have Hotfix 225595_enu_i386.exe or a later version installed on the Exchange server before running the Quota Message Service.

Henrik Walther has written an article about this tool in the past: Customizing Mailbox Limit Warnings with the Quota Message Service for Exchange.