Just like every guide says, I put bBorderRegionsEnabled=0 in my Skyrim prefs ini file. But the invisible barriers are still there, turning me back even if I use noclip. I edit .ini files all the time, so it isn't a newby mistake of some sort.

What could be the problem?

It doesn't work with me either. When I get about 20 yards over the border I get stuck. Now I can't even get over the border.