if you have cleared/removed the Cookies from your browser, or are unable to, and the problem with logging in still persists then I have a couple of things to try.
Next time you are Logged into the Forum, select the Logout button that you see under your name at the top of each page. And then log back in again and check the 'Remember Me' box. By actually logging out, rather than just not doing anything when you have finished on the Forum, may reset things for you and you will be remembered for another 60 days.
When you are next required to Login, scroll to the bottom of any page and select the word 'Login' that is in the bottom left hand corner of the screen. This will take you to a different Login box where you can type your name, password and tick the 'Remember Me'. After 15 minutes of doing nothing on the forum or the next day, see if you have to login again.
Sorry Terry, been kept away from the entertainment desk... yes short time probably less than 15 minutes. Problem still persists, tonight almost instant after logging I was told my time had expired and logged me out. re-logged straight away and here I am "wasting time again"...