When I tried to start Livetrack this morning, I got this error. Tried to start it several times over the course of a four hour ride, with the same error each time. I had a good 4G data connection on each occasion I tried, and when I ended the ride GCM uploaded it immediately without any problem, so obviously no problem with connection between phone and GPS or to the Internet. Livetrack worked fine the last time I used it a couple of weeks ago. GPS is an Edge 1030 with FW 4.0 and phone is a Pixel 2 with latest Android and GCM 4.6.4, and I'm just trying to send the invite to an email recipient.
I finally got it working today and past this error messages today.
BUT ... I did not see anyone that I added on the bread crump map. Neither can that party see me. We rode for 7 hours. Usually the interested party will show up on the map within 10 minutes.