All posts in the topic Dealing with Unwanted Posts (Short link)
From time to time, we are asked if there is a way to delete posts from an online group. Unfortunately, we do not yet have a feature that enables this. The best way to handle the problem of unwanted posts is prevention, and switching on moderation in your group is a good way to do that. When we do have a feature to handle unwanted posts in the archive, it will enable the author of a post, and a group administrator to hide a post so that it does not appear in the web interface for a group. The system will also create a clear record of what has been done, visible to the author and administrator. It will also enable posts to be "un-deleted", if they are deleted in error. Unfortunately, this will not solve the problem that all posts are emailed to group members, and there is no way to delete those emails. Those who are interested can view and comment on the item relating to this in the GroupServer development issue-tracking system. https://svn.iopen.net/projects/groupserver/ticket/316
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