Problem with Restart Schedule after upgrade?

Problem

After upgrading from 7.9 XenApp environment to 7.12 the delivery group restart schedule is no longer working if Notification Message is selected.

Solution

Complete the following steps:

1. Download the private LC6766. (Contact Citrix Support to request this private).
2. Connect to a test VDA 7.12 and stop the service Citrix Desktop Service.
3. Navigate to “C:\Program Files\Citrix\Virtual Desktop Agent”.
4. Rename the existing BrokerAgent.exe to BrokerAgent.old and copy the private version of BrokerAgent.exe into the folder.
5. Restart the Citrix Desktop Service.

Workaround

Do not send any message while reboot schedule.
Note: If we are sending the messages then message will pop up however no reboot to the machines where session is connected.

Text is copied from this Citrix support article:
Restart Schedule Does Not Work If We Send Any Notification Message In XenApp 7.12