Sometimes when people run a forum or even on social media the long time participants will notice that they answer the same questions over and over and over... this may lead to forum rules that ban posts that are repeats of old questions.
I think this is almost always a mistake if you are trying to build a community. It's helpful and good to link to similar older posts, but nothing makes a community feel insular than being told none of your questions are new and RTFM.
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