FedEx recently changed the URL structure used to return tracking results. Simply change one item in /admin/includes/english/ship_fedex.php, from this:
define('URL_TO_TRACK1', 'http://www.fedex.com/cgi-bin/tracking?action=track&tracknumbers=');

to this:

define('URL_TO_TRACK1', 'http://www.fedex.com/Tracking?action=track&tracknumbers=');

Now your customers won't see the annoying redirect screen when they try to track the package from the email link.

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