Because your issue is not anything about the issue describe by the starter of this thread.

So someone reading this dug up zombie thread might not realize you ask a question and then begins answering the OP's questions. Or perhaps you might re-kindle and old argument that is better left in the grave.

It will always be better IMO to start a new thread. Although I'll give you credit for not doing what many do and just say "I have the exact same issue, help me". Because usually when you get to questioning them it's not really the same issue at all.

If you find a thread that is pertinent to your issue, then you can simply reference that in your thread by just linking to it.