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[Anssi]

It is a known issue with your old SketchUp version. Instructions in this thread:

SketchUp (desktop version) thinks you don't have an Internet connection

Since about a month ago there has been an increase in the number of forum posts and support requests, where SketchUp is showing a message about how you need to have an Internet connection to do that feature. The features affected would include Add location, Generate Report, 3D Warehouse, and Extension Warehouse. It also would prevent you from being able to add a Classic license, or use an existing Network license. Some extensions may be affected too, if they rely on having an Internet connection…