they're two version numbers apart -> max 9 -> 2008 -> 2009. yours should be from sometime in 2007. oh and improvements of course. ;) might sound alien today but back then they did put some worthwhile additions into releases still. max 9 i remember had huge speedups over the predecessor and was much more stable when using…
3ds Max 9 and 2009 are separate releases. (Just FYI) Both are pretty old. Unless you are using 2009 on Windows XP or Vista, you're probably going to see glitches.