A Citrix Administrator discovers that several virtual desktops in Citrix Studio are unregistered. Click the Exhibit button to view a screenshot of the XenCenter Console. Based on the information in th

A XenServer not being a pool member affects pool-level resource management but does not directly prevent running VMs from registering with a Delivery Controller.

Maintenance mode on a XenServer host prevents new VM starts on that host but does not by itself cause already-registered VDAs to become unregistered.

VDA registration requires the virtual machine to be powered on so the VDA service can start and communicate with the Delivery Controller. If the VMs are not running, the VDA process never starts and the machines appear as unregistered in Citrix Studio. The XenCenter console would show the VMs in a powered-off state, confirming this as the cause.

Suspended VMs are in a saved memory state and are not running, but the screenshot context points to VMs that are fully powered off rather than suspended.