Firefox include the option to block cookies globally and on a per-site basis.
1. At the top of the Firefox windowOn the menu bar, click on the ToolsFirefoxEdit menu, and select Options...Preferences....
2. Click the Privacy icon.
3. Make sure Accept cookies from sites is check marked.
* If it is not checked, check mark it.
4. Click Exceptions....
5. Make sure the site you're trying to access isn't listed.
* If it is listed, click on its entry, then click Remove Site.
If you changed any settings, try accessing the web site again.