Won't stay logged in, can't log in...

Each and every time I go to my favorites and click on the Welcome to For A Bodies Only Mopar Forum "which is how I have always got on this site" I need to log on, never had to before. As soon as I exit the forum I can click right back on it and I need to log on again. Why is it only this site that I have to do this on, and it has been this way for over a week now. I am by no means a computer geek, and I thought cookies were something you ate to get fat, but it seems to me that there are a lot of members having the exact same problem on this site only. If there is definitely something that I need to do on my computer please let me know.