Systems.xml File Syntax
For correct syntax, the systems.xml file has to use this hierarchical order of elements:
<Systems>
<Default System>
<System>
<Server>
<opcdaclsid>
</opcdaclsid>
<opchdaclsid>
</opchdaclsid>
<opcaeclsid>
</opcaeclsid>
</Server>
</System>
</Systems>
Many of the elements have attributes that define the settings for the client connection Systems.xml File Attributes.