Okay, that confirms a theory I have about the NSFW tags. If the caption you use might be seen as racy (in @nadine’s case, she referred to naked trees), the forum rejects the photo. Apparently, in @bikingjenn’s case, “more fun” was seen as a little too racy for this forum (!). And then the forum remembers the rejection, so if you try to post that same photo again, it will be rejected even if there is no caption or a completely different caption. But if you modify the photo (@nadine cropped out a little of it) or if a different person posts the exact same photo, it goes through.
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