I need to bump this topic,
This issue happend to me today, on dashboard under "My channels" I've got this message with "There was an error retrieving channel information", just after I manually tried to update my JSON feed.
When I go to "My channels" I am redirected to this:
Already tried to clear cashe/cookies etc. on Chrome and Safari, I am on Mac system if this matters.
#EDIT: A day later out of nowhere it happens to work as before 😉