I do have the same issue since the latest update of Firefox, so that it could be a "bug". This hasn't happened with previous versions.
I'm currently checking their support database and forums to see whether this issue has already been brought up. If I don't find anything, I'll report the issue and see what the developers say.
I haven't found any related issues mentioned, so that I've made this report in case you wish to see the follow up:http://support.mozilla.com/en-US/forum/1/495548
The reply I got there has helped
It's really a strange coincidence with the upgrade of FF and the cookie issue.
I hope that the following steps will help you to resolve the problem, too:
- Disable your add-ons that might interfere with accepting cookies (in my case NoScript and AdBlock Plus).
- Delete cookies and history on restart of FF.
- Log into your Hotmail account and accept all cookies. Log out.
- If successfully logged out, enable the add-ons again, and restart FF.
Edited by Mysterysgames, 08 November 2009 - 10:42 PM.