The FAFSA web site is designed to reject browsers it does not yet support. You could set Firefox to "lie" to the site and tell it you have an earlier version. However, considering the nature of the site, you could end up spending a lot of time working on forms and then not be able to complete them, which would be a major bummer.

So... I suggest using Internet Explorer for this site. If you deleted or hid your IE icon, you can start the program using

Start > Run > iexplore.exe

You can also try installing the following Add-on to display in a tab in Firefox.

• The Add-on uses your currently installed version of IE to display the tab, so, for safety sake be sure you have IE 8 or higher installed on your system and that it is currently updated through Microsoft Update.
• I successfully use this extension to do the Windows/Microsoft Update every month using Firefox.
• IE Tab + (formerly Coral IE Tab): http://coralietab.mozdev.org/installation.html