The solution offered by @colin in the following thread (ON_LINE_TEST_URL=https://www.bing.com) worked for me:
SketchUp (desktop version) thinks you don't have an Internet connection
However, no actual report can be generated. When the Generate Report function is first activated, the following error window appears:
When I click OK, the Generate Report window fills in with its various controls and seems to be OK. When I attempt to Run a report, the same error window appears. When I click OK on that second error, the Generate Report window contents change to the SketchUp logo and the red text “Generating Report…” and that’s all. Nothing else happens with the report. The remainder of SketchUp is fully responsive, but the Generate Report window sits there doing nothing other than telling me it is generating my precious report (I waited for ten minutes for a trivial report).