Garmin Connect does not load activities

What do you mean by it does not completely load? If all you're seeing is the icons on the left hand screen and the main pane is blank this is indicative of a problem caused by programs like ghostery etc and/or your browser settings blocking the download. Do you use any program like ghostery? Which browser are you using?

Hudson_Mbong, have a look at this post. It sounds like the same issue as many of us have had.