Error Loading Polygon or Error Loading GeoPin when TNP starts.

When a data file becomes corrupted, Terrain Navigator Pro does its best to recover from the error. However, in some cases (usually with files that are not in-use) TNP fails to recover the file. This can cause repeated error messages of "error loading polygon data", "error loading geopins" or similar messages when TNP starts.

This can be corrected by deleting the corrupted files so that TNP can rebuild them.

After exiting Terrain Navigator Pro, open the following folder on the PC:
C:\Users\<your username>\AppData\Local\Maptech\Terrain Navigator Pro\Projects

Note that the AppData folder is a hidden system folder. Turn on "show hidden files and folders" (in Windows 7) or "Hidden items" (in the View tab in Windows 8) to access the AppData folder.

The Projects folder contains a folder for each of your projects. In most cases, this error occurs with the [Default] project - however, you may be using a different project. Open the folder that matches your project name.

If you are receiving an "error loading polygon data", delete the following files:

If you are receiving an "error loading geopin data", delete the following files:

Restart Terrain Navigator Pro and the error should no longer appear.

I'm not using Projects. What are they and how can I use them to better manage my layers of markers, tracks, etc.?
Projects allow you to create groups of layers and create efficient use of the features offered in Terrain Navigator Pro. For details, check out:

I am not a computer expert. Should I attempt to delete these files?
Only someone with moderate computer skills who is familar with copying, moving, and deleting files should attempt this procedure. If you do not have an IT professional within your organization that can assist you, please call us at 800-627-7236 and we will offer a remote session via a secure Internet connection to delete these files. 

General Questions (FAQs) and How-To Answers

  1. Getting Started with Terrain Navigator Pro
  2. Coordinates: Definitions and Overview
  3. What are Layers? What's the difference between markers, routes, tracks, etc.?
  4. Organizing Layers with Projects
  5. Managing Projects, Splitting the Default Project, Project Synchronization to TNP Mobile/Web, and Other Tips
  6. How do I obtain an area measurement?
  7. Street Layer. Can I turn it off? What about updates/inaccuracies? (And other common questions)
  8. What is a MapPack and how do I use it to show photos when TNP has no Internet Connection?
  9. Transferring Project Layers to a new PC
  10. Red Triangles on the maps. Can I toggle them off? (And other common questions)
  11. Apple Mac OS and Terrain Navigator Pro
  12. How to Disable Registration and Subscription Renewal Notices
  13. Adding Land Use, Boundaries, and other GIS Information to TNP
  14. Using Existing Markers to Create a Route in TNP
  15. Creating (or Projecting) Routes via Bearing/Distance (metes and bounds) - by Azimuth or Quadrant bearings.
  16. Adding Waypoints within a Route; Appending Routes Together
  17. My Markers, Routes, etc., are way too big (or too small.) What's going on?
  18. Attaching Maps to an Email
  19. How do I make TNP open my map every time it starts?
  20. Recording 3-D Video Clips
  21. Keyboard Shortcuts
  22. Error Loading Polygon or Error Loading GeoPin when TNP starts.
  23. TNP System Requirements
  24. What Are the Benefits Included in the Annual Subscription?
  25. Video and Printer Driver Updates: How to apply them to improve Terrain Navigator
  26. Repairing a Corrupt Map Engine (black maps, not responding, etc.)
  27. Google Earth doesn't interface properly with TNP

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