The post in question matched a pattern of spammers wherein they'll post something completely valueless to an old thread along the lines of "thanks for posting" or "that was very useful, thanks", as a means to spam their signature. We delete those as violations of the following Keep It Spam-Free clause: "Do ensure that all posts contain relevant content and substance and are not simply vehicles for external links, including signature links"
It seems you got caught as a false positive, so I'll undelete that post for you. Just keep in mind that if your signature looks spammy, there's a risk of being seen as a spammer on a case-by-case basis until you've developed a good reputation in the community. It would be a good idea to familiarize yourself with our rules. They're mostly common sense, but it helps to know what moderators look for.
I never worried about those things you told. Next time I'll be more specific about the content I am posting. Beacause I am new to the forums so I might be unknown for the problem occuring with the spam post. I am not going to add any signature till I get familiar to the forums and get all the information about forums.