Read Thread: Letterboxes on Interstate/Highway Search
The problem seems to be that custom locations are treated as mystery locations as the software geocoder does not know where a specific long/lat is located in the human world, as crazy as that sounds. I noticed that I had several boxes listed as mystery boxes because I used custom coordinates as the location instead of a street address and city name. changing the location in the clues to the nearest town and state actually helped get the boxes to show up in the right searches.
Actually you just need to edit the custom location. I have done this about 10,000 times (or more; Ryan would have to run a query to see my total number of custom locations).
Basically, save the coordinates as 50.655251, -3.977487 then click the pencil then 'Edit Custom Location'. MOST of the time AQ will then successfully look up the city/state information. If not, do it manually.
In either case, you now have a letterbox listed as 50.655251 -3.977487, Okehampton, Devon, England, United Kingdom so it will show up in a search correctly.
The problem is that you first have to ADD the coordinates to the AQ database. Then it will try to match the AQ entry to the online ones. AQ isn't capable of doing both at the same time.
Ok, thanks! I didn't know that about custom location. Sometimes I don't know how great my clues are xD so I like to include the pin as a starting point. Haha.