i hve a problem

I dnt know where to post this...so i posted it here..sorry if it does nt belong here.

well my problem is:once i login in my name and post few things....after some time,when i want to reply to a particular post,i suddenly get logged off.i have to keep on logging in again and again.i dnt seem to understand whts happening.

also since i have the net at home,i keep going to the forums.i expect to have an autologin like before.(automatic log in)

but thts not the case.everytime i open the page,i have to login freshly.i dnt log out anytime.

why is ths happening?pls help...