Closed questions (or "On hold" questions) cannot be answered, but can be edited to make them eligible for reopening.  See [What does it mean if a question is "closed" or "on hold"?][1]

Close voting can be done via:

 - The web site, sometimes aided by tools found here on Stack Apps.
 - The official (i)phone apps.
 - The [API][2].

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See also: [The Community user deleted my question! What gives?][3]


  [1]: https://stackapps.com/help/closed-questions
  [2]: https://api.stackexchange.com/docs/create-question-flag
  [3]: https://stackapps.com/help/roomba