I’ve made a perimeter around my PCB int he Edge.Cuts layer, and run a RDC which come back with no errors. However, when I go to View–>3D View I get the following error:

“O_ERROR: Unable to find the next boundary segment with an endpoint of (154.40406 mm, 119.9388 mm).
Edit Edge.Cuts perimeter graphics, making them contiguous polygons each.
from specctra.cpp : ThrowIOError() : line 144 Unable to calculate the board outlines.Therefore use the board boundary box.”

I’m confused what the problem is, how to fix it, and it my PCB is fine to be made if my RDC came back with no errors. Any advice appreciated, thanks in advance!

Polygons?
You should make an outline, not polygons. Use the line tool and make sure to double click the first point when you want to finish the shape and complete the outline.
You can use arcs too but that is tricky and you have to make sure to use grid to snap things exactly together.

Thanks for the answers, you both were correct. I had set my grid to small and when I re-drew it and right clicked “end track” I no longer got that problem.

That is very good to know. I had been assuming that continuous meant that the ends had to be coincident at the smallest interval that the program can measure. Thus I hadn’t even tried hand drawing arcs into my board outlines.