During the normal operation of your Windows desktop or server desktop you see the following dialog message
"A program running on this computer is trying to display a message"
"View the message"
"Ask me later"
Services and system processes run in session 0. Prior to Vista, the console (first logged on user’s desktop) ran in session 0 as well. Vista introduced session 0 isolation to protect services from elevation of privilege exploits from the console desktop. Now, the first user’s desktop runs in session 1.
Interactive Services Detection (the blinking button on the taskbar) is a mitigation for legacy applications that detects if a service is trying to interact with the desktop. This is handled by the Interactive Services Detection (UI0Detect) service.
When you choose “View the message”, you are taken to session 0’s desktop and you can only interact with the dialog or message that services have tried to display on the desktop.
If you run a Kaseya agent procedure as SYSTEM, and the command that you are running displays a message - maybe a "Click OK to continue" or simply a command prompt message, then this may trigger this situation
WORKAROUND / RESOLUTION
This is a Windows feature and is not a problem - it is the way that Windows Vista and later work.
However, this can be annoying and raise questions from customers that are affected.
To disable this, stop the "Interactive Services Detection" service in the Windows Service applet. This service should be set to Manual by default, but you may want to set this to "Disabled".