World of EUC

You could schedule a powershell task to get the machine names using Get-BrokerDesktop|select machinename, then use net send to send a message to all users on each machine.

Hmm. net send no longer exists, but you can just use Send-Brokersessionmessage instead:
<https://developer-docs.citrix.com/projects/citrix-virtual-apps-desktops-sdk/en/latest/Broker/Send-BrokerSessionMessage/>

asnp citrix*
$sessions=get-brokersession
Send-BrokerSessionMessage $sessions -Title "Test" -Text "This is a test message" -MessageStyle Information

excellent, I'll test this out.

Thank you Scott.