System Configuration : Preferences : Display Preferences : Warnings and Dialogs

Warnings and Dialogs
Reset “Don’t Show This Again” Settings
If you have made any changes by selecting the Don’t Show This Again setting for any dialog in Pro Tools, you can click this Reset button to revert to the default settings.
Show Quick Start Dialog When Pro Tools Starts
When selected, Pro Tools shows the Session Quick Start dialog on launch. Deselect this option if you do not want to see the Pro Tools Quick Start dialog on launch.