Loading Maps onto Computer

[rah]

I am having a serious problem loading topo maps from my computer onto my GPS.  I have been at it for at least 2 hours - probably more - and in that time have loaded two topo maps onto my GPS (had three ready to load).  The rest of the attempts elicited a response of "This device already has your latest maps fully installed" even though I have one topo that is yet to be loaded (also gave that message on my first attempt). I am thinking this may be a computer problem and not a "transfer" problem.  I never had a problem of this nature with a previous computer.  Any ideas? Thanks much.

[-Oz-]

Which GPS? What maps? And did you try to follow this tutorial: http://www.gpsfiledepot.com/tutorials/how-to-load-maps-on-my-garmin-gps-unit/