Have you tried re-associating all of the file extensions ?

What file are you working on? Is the file you are working on have the right name? Sometimes I has had error issues because the file(s) had the wrong name on it. If you are trying to download Firefox, go to Mozilla.org for the full install.

If you are trying to install Firefox then try this:

Download and save the full Firefox installer to the desktop and start the installation with a double-click on the desktop icon.

You can find the full version of the current Firefox 26.0 release in all languages and for all Operating Systems here:

• http://www.mozilla.org/en-US/firefox/all.html