Not be able to access grass map

Hi, grass users!

I'm a novice in grass world, and got in trouble.
   The trouble is that I could not access any map in the mapset.
   I can see map files (just see), but whenever I was trying to
   access those map files, I got zero values. Of course, I could
   access those maps before, but from this afternoon I could not
   do anything with the map files.

Please help me. I must do something until Thursday.

--
Seungchan Kim (dolchan@agen.tamu.edu) |=|
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