There are three formats of Latitude/Longitude: Degrees/Minutes/Seconds (D M S), Degrees/Minutes (D M.M) and Decimal Degrees (D.D). The default setting in Terrain Navigator Pro is Degrees/Minutes/Seconds. However, some GPS units default to Degrees/Minutes. If your reading looks something like: 44 16.84N 69 2.73W, your GPS is giving coordinates in Degrees/Minutes.
To correct the situation, you have two choices: change your GPS unit to Degrees/Minutes/Seconds, or change Terrain Navigator Pro to Degrees/Minutes. Refer to your GPS documentation if you want to change your GPS readings to Degrees/Minutes/Seconds. To change Terrain Navigator Pro to Degrees/Minutes, open the File menu, choose Preferences, Coordinates, and change the Format of the Primary Coordinate Display to D M.M'.
Also, be sure that the Datum used by your GPS matches the Datum used in Terrain Navigator Pro. Most GPS units default their datum to WGS84. In the Primary Coordinate Display Preference in Terrain Navigator Pro, also set the Datum to WGS84 (or whatever Datum the GPS is using.)