The information about how the licenses have been distributed to the managers is stored on the ESM console in an XML file. The XML file resides at the following location:

<console_installation_dir>\Database\ESMLDInfo.xml

A default XML file is shipped with Symantec ESM and it gets updated as and when you install the licenses. If this file is not present or corrupt, you cannot manage the Enterprise Licenses from the ESM console.

Make sure that you backup this file regularly and do not edit it separately.