Considerations for Installing 32-Bit Software on 64-Bit Windows Computers

Before enabling 32-bit installations on a 64-bit Windows computer, review the following requirements and limitations.


If the 64-bit computer where you plan to install a 32-bit agent has other Commvault software installed, you must install the 32-bit agent on a new Commvault instance. You can have 32-bit and 64-bit agents running on the same computer, but they must be installed on separate instances.

For more information, see Enabling Multi-Instance Installations.


You can install a 32-bit agent on a new instance from the CommCell Console. During the remote installation, you can select the options to install 32-bit agents and to install in a new instance.

Windows File System Agent

The 32-bit version of the agent does not support the following operations:

  • VSS backups and restores.

  • System state backups.

  • Full system restores for RSM, RSS, Terminal Services, and disk quota.

Exchange Agents

If you want to install both 32-bit and 64-bit Exchange agents on a 64-bit computer, use the following approach:

  1. Install the 64-bit agent.

  2. Install the 32-bit agent on a separate instance.

    The new instance contains the 32-bit MAPI-based Exchange agents. You can use the 32-bit MAPI-based Exchange agent along with 64-bit Exchange agents.

If you plan to install a 32-bit MAPI-based Exchange agent, you must satisfy the following requirements:

  • You must have the 32-bit version of Microsoft Outlook 2007 or later installed on the computer where the agent will be installed.

  • If you plan to install the OWA Proxy Enabler on a separate instance to support the functionality for 32-bit Exchange agents, the client name that you specify during the installation must be the same as the client hosting the 64-bit instance.

SQL Server Agent

The 32-bit version of the SQL Server Agent does not support VSS backups and restores.