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This logical disk has less than 3 GB of available space

[This topic is intended to address a specific issue called out by the Exchange Server Analyzer Tool. You should apply it only to systems that have had the Exchange Server Analyzer Tool run against them and are experiencing that specific issue. The Exchange Server Analyzer Tool, available as a free download, remotely collects configuration data from each server in the topology and automatically analyzes the data. The resulting report details important configuration issues, potential problems, and nondefault product settings. By following these recommendations, you can achieve better performance, scalability, reliability, and uptime. For more information about the tool or to download the latest versions, see "Microsoft Exchange Analyzers" at https://go.microsoft.com/fwlink/?linkid=34707.]  

Topic Last Modified: 2007-09-19

The Microsoft Exchange Server Analyzer Tool queries the Win32_LogicalDisk Microsoft Windows® Management Instrumentation (WMI) class to determine the value for the FreeSpace key for disks that have the Win32_LogicalDisk DriveType key set to 3 (which indicates a local disk). If the value for the FreeSpace key for a local disk in an Exchange Server computer is less than 3 GB, a warning is displayed. It is recommended that all disks in Exchange Server computers that contain mailboxes have at least 50 percent capacity free at all times.

Having sufficient disk capacity is critical. When a database disk runs out of space, the database will go offline. When a transaction log disk runs out of space, it will cause all of the databases in that storage group to go offline. Provisioning additional space is often hard to do quickly, and performing offline compaction to reclaim space can take a long time. In most cases, running out of disk space results in an interruption of availability of one or more databases for a period of time that typically exceeds most recovery time objectives (RTO).

To correct this warning

  1. Delete unnecessary files from this disk to free up disk space.

  2. If the disk that has less than 50 percent space free contains data that can be safely moved to another disk (such as mailboxes, or the Windows pagefile), perform the steps that are required to move the data.

  3. Add disk capacity to the Exchange Server computer.

For more information about moving mailboxes with Exchange Server 2003, see the Microsoft Knowledge Base article 821829, "Moving Mailboxes in Exchange Server 2003" (https://go.microsoft.com/fwlink/?LinkId=3052&kbid=821829).

For more information about moving mailboxes between Exchange 2000 Server and Exchange Server 5.5, see the Knowledge Base article 328810, "Moving mailboxes between servers" (https://go.microsoft.com/fwlink/?LinkId=3052&kbid=328810).

For more information about setting mailbox limits with system policy on Exchange Server 2003, see the Knowledge Base article 822938, "HOW TO: Use System Policies to Configure Mailbox Storage Limits in Exchange Server 2003" (https://go.microsoft.com/fwlink/?LinkId=3052&kbid=822938).

For more information about setting mailbox limits with system policy on Exchange 2000 Server, see the Knowledge Base article 319130, "HOW TO: Use System Policies to Configure Mailbox Storage Limits in Exchange 2000" (https://go.microsoft.com/fwlink/?LinkId=3052&kbid=319130).