Garmin GPSmap shows wrong location on built-in map - help!

[KiwiLondon]

I have a Garmin GPSmap60CSx. Just today it has started showing my position on the built in map as being out by at least 0.3miles. The OS postion appears to be right, though when I change the units to Lat/long that looks a bit out too. Has anyone else had this problem - how did you solve it?

I also had problems loading trip & waypoint manager. it corrupted by registry and now I can't restore the PC. Likewise, has anyone else encountered this?

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