WP8.1 IE11 sometimes not working, at all?

On my 520, sometimes IE11 will just stop working and keep reporting DNS errors. Internet connection still works in all the other apps, just not in IE. It happened to me maybe 4-5 times already but I have not yet established a pattern (was I on wifi, or 3G and such). Closing IE from task list does not help.Restarting the phone does not help.

Is anyone else experiencing this? Has it been documented?