Best, Try to perform the mandatory navcore update on the GO5100 m.b.v. MyConnect. - Original USB cable. - PC runs on Windows 10. - Latest version of MyConnect installed Download succeeds, connection via MyConnect is set up, notification update is performed, at 24% the USB connection is terminated. The following message appears on the PC screen: Connect your GO5100. The GO5100 still says: Keep your system connected, The update will continue in a few moments. After waiting a while, the PC and GO5100 will be connected again, but the update will not continue. Connection is broken again, history repeats itself. Anti-Virus disabled, no solution. Other USB port used, no solution. Thank you for thinking along.