The "Network connection lost" message indicates that the network connection between the Zero client and PCoIP Host Card or VMware View virtual desktop host is down or disrupted.  This provides an indication to users that the information on their display may be stale.  There is a fast trigger for this message which is a requirement for real-time sensitive applications such as command and control and investment trader workstations.  

The fast trigger, the "Network Connection Lost" message can be falsely triggered repeatedly by a virtual machine host that is busy due to process scheduling on the server.  As such, it is recommended that this message be disabled for connections to virtual desktop sessions.  Firmware 3.2.0 or newer provides the ability to disable this message notification.

Common steps for avoiding this message - make sure:

• That the Ethernet cables are connected properly to the PCoIP Zero Client, PCoIP Host Card, and network devices (e.g., switches).
• That the network is up. 
• That the esx server has enough processing power to service the VM's within best practices for VDI.