I've just become an owner of a 405HR, and I have the same problem as many other people it seems.
Not only do I get "No map data found for this activity. "
Also the timing and heartrate graphs are empty.
As there is no map data it seems, I first wondered that I did not use the gps function on the watch correctly (wich is "on" ofcourse), but this seems strange as the distance I ran is correctly stated.
This problem occurred on both runs I did using the watch so far...
Clearing cache does not help...
Link to my activity:
http://connect.garmin.com/activity/11579096
Any help is highly appreciated!