Occasionally, even though a topic has been closed, it's desirable to go in and modify your existing posts within that topic.
An obvious example would be to fix broken links, but there may be other reasons as well.
If there's a case where fixing a link in such a topic is critical, contact a moderator. There shouldn't be much other reasons - they're closed for a reason.
Then you should stop closing the solved/rejected bug topics. There is a difference between a solved bug and an imperious end of conversation. This conflation comes from treating a forum as a bugtracker.
Instead, edit the topic title or move the bug topic.
-- Simon