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Necroposting isn't strictly against the rules, but it's just one of our guidelines.
Quote:Do Not Necropost.
Necroposting is the act of posting a new reply to a thread that hasn't seen activity for a long period of time. Our specified limit in terms of necroposts is 30 days. That means if you post a reply to a thread that hasn't had any replies for more than 30 days, you are necroposting. We appreciate that checking the last reply date is hard, so you will see a warning notice whenever you try to reply. If you think you can make a new thread out of your reply, please try to do that instead.
Necroposting isn't strictly against the rules, but it's just one of our guidelines.