I'm signed up with more online forums than I would care to count.  It seems every week I sign up with a new one to get advise on some new software or something.  I used to be very selective and signing up felt like a burden, but now I just sign up whenever I need an answer.

But something I've noticed on a few forums is an attitude or even rules about reviving old threads.  The rule being, 'if it's old, don't reply to it'.

I've seen people criticed for replying to a thread that hadn't been posted to in months.  In one case it was my thread relating to a method of how to achiive something in PHP.  I came in to defend the 'revivor' since I was still interested in peoples input.  I mean, I was still a member of the forum, I still use PHP, a solution was never found, I was still interested in any answers for future reference, and some guy was trying to stop him from providing me with an answer.

I didn't understand why that thread should be considered no longer relevant just because it's 12 months old.  Even if it wasn't relevant to me any more, it had became relevant to the revivor and will be potentially relevant to anyone who has the same issue in future.  Why would you discourage someone from giving an answer that might help someone, even if it's not the person who started the thread?

It seems to me, that reviving an old thread is better than starting a new one.  Reviving an old thread means you've attempted to find an answer.  Reviving an old thread is the best place to get an answer because in most cases the people who participated in the past will be notified.  Reviving an old thread will help create one concise source of information rather than having a lot of threads that have inidividually gathered very little attention and flood search results.