While I have never experienced this problem at FlyerTalk before...I have experienced problems with cookies on other sites in the past.

Provided that no changes in the software to FlyerTalk were made...there were probably security setting changes within Windows (I'm assuming).

The thing is that you do not need to actually change them for them to change. (What were they thinking?) If you use Automatic Updates in Windows - or if you have downloaded Windows Update files from windowsupdate.microsoft.com ... there is a decent chance that your security settings have been changed.

There are many different updates that could change your security settings...but most notably are "security" updates or "internet explorer" updates (or upgrades!).

To change your Internet Explorer security settings, go to Tools -> Internet Options. Alternately, you can go to Start -> Settings -> Control Panel -> Internet Options.

The problems you are experiencing could be caused by settings related to cookies.

Just a thought! Be warned that changing the wrong settings could allow someone bad to harm your computer.