I'm receiving that error at the section in the tutorial where you're deleting 4 borders which make up the end of the wrist. I'm doing it exactly like the tutorial.

If I only extrude once and don't pull anything out, and simply scale the vertices down and merge them - then deleting those edges works fine...

However - this problem occurs after I extrude those edges out 3 times and then scale / merge / select those 4 edges.


Any idea of what this problem could be? I've been tryin to figure it out for over an hour!

Thanks!