Mark all as read isn't working or that some posts don't mark as being read for you? I have found that how I exit a post makes a difference in whether or not it gets marked as read. I need to avoid hitting the back button. Sometimes even if I go from the post being viewed directly to the main forums menu, that post won't mark. I have my best luck by exiting the post to that forum's start page. Message marking doesn't seem to be broken for me now but it does have its quirks from time to time.

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