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Use start session scripts only if you need to configure desktop policies before a session starts.
As a best practice, use the Horizon Agent CommandsToRunOnConnect and CommandsToRunOnReconnect group policy settings to run command scripts after a desktop session is connected or reconnected. Running scripts within a desktop session, rather than using start session scripts, satisfies most use cases.
For more information, see “Running Commands on Horizon Desktops” in the Configuring Remote Desktop Features in Horizon 7 document.
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