Symptoms

When users attempt to launch a published application via Parallels Client, below error is displayed:

Cause

Terminal Server Agent is installed on Windows Server 2008/2008 R2 OS.

Resolution

• Logoff the session for the particular issued user.
• Open the RAS Console > Farm > Terminal Servers > Properties of the Terminal Server you are publishing issued resource from.
• Switch to the Agent Settings tab.
• Tick the option: Use RemoteApps if available.
• Apply the settings.

NOTE: if multiple Terminal Servers are effected, this change needs to be done on all of them.