When connecting a TwoNav GPS device to a computer via USB cable, Land will detect it and display it in the 'Devices' branch of the data tree to access its internal files:

For Land to display the device, it is essential that the device appears in the Windows File Explorer (or in the Mac Finder), and that its internal folders can be accessed.
If this is not the case, the 'Devices' branch will appear empty. For this situation, consult My GPS device is not detected by my computer.
 

Device error

If the device appears as 'Device error', instead of the name of the TwoNav GPS device (Roc, Cross Plus, Terra...), it means that Land was unable to correctly read the device information:

This may be due to several reasons:

• Old version of Land: 
  Current TwoNav GPS devices are not recognized by very old versions of Land (Land 7, Land 8...).
   
• Security restrictions on the computer: 
  Some computer settings may prevent proper reading. For example, on Mac computers, within System Settings > Privacy & Security > Files and Folders, you will find Land 10 and its access permissions. 
  The Removable Volumes permission must be enabled for Land to read the device:
  
   
• Android devices (TwoNav App): 
  Most current Android devices do not allow access to the information, so generally Land will not be able to display the content of the TwoNav App. In some cases, it may also appear as 'Device error'.
   

Alternatives

Remember that, besides Land, there are other ways to add files to TwoNav devices:

• Add routes to the GPS device / Add routes to TwoNav App
• How to install Maps
• How to open personal maps in the TwoNav App