VDA Registration failed due to the Virtual Delivery Agent software installation on the machine is missing or not functioning correctly. This issue can occur if the software was not installed correctly or the installation got corrupted.

To resolve this issue:

1. Open Control Panel - Programs and Features and confirm that the Virtual Delivery Agent software is listed as installed on the machine.
2. If Virtual Delivery Agent is already installed, repair the VDA installation or uninstall the VDA software and install it back as described in Citrix eDocs Install VDAs document. Be sure to download the version appropriate for the machine's operating system. Refer to Citrix eDocs for system requirements for Desktop and Server VDAs .