Instructions
Launch your computer's Web browser by clicking its icon on the desktop, and navigate to the Geocaching website.
Click the "Sign In" link at the top of the page and to the right of the Geocaching logo.
Enter your username and password in the relevant boxes and click the "Sign In" button.
Hover the mouse pointer over the "Your Profile" menu to reveal its options. Select "Geocaches (Yours)" from the "Your Profile" menu. Details of all of your geocaching logs will be displayed.
Click the "Didn't Find It" link in the "Your Geocaching Logs This Month" section. A list of caches you did not find will be displayed. The number of DNFs you have accrued will be displayed under the title "Your Geocaching Logs."