Go to Delivery Controllers and view the application status: If you see the session at the pre-login status and then it vanishes then that means that Session is successfully trying to load but something is not letting is keeping it from the successful load.Go to StoreFront and try to load the application from the StoreFront web host web URL, if the slowness is still there then it eliminates the possibility of any client-side network slowness issues posed between Netscalers and Studio.Here are the additional troubleshooting steps. The user sees application starting notifications, and after that, the application is never actually launched.The application appears to launch, loads up to 80% then immediately closes.The issue can present 2 different symptoms: There are no errors presented to the user, Event Log of the XenApp server or VDA hosting the application reports the following “EventID:20499 – Remote Desktop Services took too long to load the user configuration from server for the user XYZ”. Published Applications or Desktops don’t launch, or disappear during launch.
