Do you have any other browsers installed on your computer? You
could try it in Firefox or Google Chrome and see if you have the
same problem. Are you running any strict antivirus or antispyware
apps on your computer? It's possible one of those is interfering
with the cookies as well.
The security system is the only thing I think could be causing
it. I know the site is working fine for me when I log in, and I
haven't had any other complaints about cookie errors from any other