Guild Wars 2

I go to the little green star location just north of Concordia, and click “Yes – enter instance” to start this step of the personal story. It goes to the loading screen for the story step. It stays on the loading screen for several minutes, with the little yellow progress circle at the bottom right continuing to turn. Then the game window closes and sends me to my desktop, where there is a Guild Wars 2 error window with the message
“A disk-I/O error has occurred!
Guild Wars 2 will now terminate.”
I’ve tried this multiple times, including making sure the dynamic events in the area were not currently active, and this happens every time. I am unable to do this story step, and can’t progress in the story.

Any ideas for things I could try? All recent patches have applied successfully.