In your main EverQuest II folder, delete or move any folders that begin with logincache (logincache-us, logincache-eu, etc.) then immediately log in to Character Select on each of your accounts (click PLAY on the LaunchPad without choosing a character.) Reopen the utility. Please post again if you're still getting the index outside of array bounds error.
Edit: Here is a more detailed post for fixing
Code:
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System.IndexOutOfRangeException: Index was outside the bounds of the array.
at DarqUI_Unified.QS_Ops.Quick_Start(Boolean redisplay, Boolean suppressnocharwarning, Boolean avoidserverlist)
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