Magellan-mapsend topo loss of detail was working fine

Hey I am having trouble with Magellan software for GPS
specifically Mapsend topo for the united states, had been
using for 5 months no trouble then on last use all detail
on topo maps have disappeared, have totally erased and
reinstalled software multiply times, reset video card G-
force5200 pixel# and bit color, updated new drivers,
called Magellan multiple time, no help never seen problem
before. Ran norton utilities, register cleaner to remove
unused items, cd will load into windows ME and xp home no
trouble.
Apparently something or program has changed since i last
used software, no new programs added or conputer
configuiration change was made.
Any suggestions would be aprreciated.
Thanks