Hi, yesterday my GT31 suddenly completed locked. It stay on one screen, the one with history max 10 sec, i couldn't unlocked it anymore or turn it off. The only solution was to take out the memory card. Then i put it back in, it started a new session again. Today, at my computer, i look up the SBN file and it had zero bytes in it. It said, when i opened it in GSP results,  Trackpoint plot   -   speedovertime.

What went wrong? Do i have to make some adjustments in my settings to avoid this??
Rogier... see the previous discussion

the Navi  appears to lock up occasionaly for no obvious reason...  only way to fix has been let the unit run flat .... then  recharge and it should start up ok again ....   but any time this happens there is normally no data saved ...
Thx Chris, wasn't aware it was about same topic. Will read it. If new things will occur, i will post again to inform.
cheers Rogier