To clear the cache and cookies in Mozilla Firefox:

(Note: These directions are for the most recent version, older versions should be almost the same after you get into the options menu)

1.       First, open Settings: (Found in the Menu at the top right of your browser)

2.       Click on Privacy & Security, select Cookies and Site Date

3.       Click on Clear Data

4.       Click clear

5.       Click Ok, Close Firefox, Re-open and try again.