Try resetting your preferences: Close InDesign. Then hold down Ctrl + Alt + Shift (Windows) or Cmd + Ctrl + Opt + Shift (Mac), and relaunch InDesign. Respond in the affirmative to the dialog asking if you really want to replace the preferences.

Why isn’t my Adobe InDesign opening?

You can try the quick way of resetting on a PC which is to hold down Ctrl + Alt + Shift when launching InDesign and respond affirmatively when asked if you want to reset. There have been some recent reports that the window asking if you want to reset is not popping up but that the prefs are being reset anyway.

Why won’t my Adobe InDesign open on Mac?

Try deleting your InDesign preferences and see if that makes a difference. To do so: For Macintosh Users: The User Library folder in which InDesign’s preferences are stored is hidden by default on most Macintoshes. Please make sure you’re using the latest version of Adobe InDesign for better experience and performance.