Firstly, empty your cache and try again.
Emptying of the cache
In IE8 - Click the Safety button at the top right and click 'Delete Browsing History', check all the box and press 'Delete'.
In IE7 - Select Tools -> Internet Options and click the General tab. Click Delete browsing history and delete temporary internet files.
In Firefox - Click Tools -> Clear private data. Again select all the boxes and press delete.
In Safari - Click Safari -> Empty cache.
If this doesn't work, try using a different browser. e.g. If you were using IE, try Firefox. If you were using Safari, try Opera.
Good luck,
Ian.