If you are planning to upgrade to ePO 5.3.x, this document will provide you with useful links and a video that illustrates the main upgrade steps.
The video is meant to give a general idea of the upgrade process and does not cover all possible scenario.
McAfee KnowledgeBase - ePolicy Orchestrator 5.3 supported product
McAfee KnowledgeBase - Supported Platforms, Environments, and Operating Systems for ePolicy Orchestr...
McAfee KnowledgeBase -
This article provides information on upgrading ePO 4.x to ePO 5.x while migrating from a 32-bit to a 64-bit operating system using the Upgrade Compatibility tool".
McAfee ePolicy Orchestrator (ePO) page: http://www.mcafee.com/us/products/epolicy-orchestrator.aspx
McAfee Sales page: http://www.mcafee.com/us/about/contact-us.aspx
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