I get an internal error fetching site when trying to validate a card, whats wrong?

barrychapman · 2014-01-04T01:09:34.000Z

I get this error:

Fetching the page failed due to an internal error.

When trying to validate a twitter card

barrychapman · 2014-01-04T01:19:00.000Z

geoffreymccaleb · 2014-02-14T15:13:16.000Z

Getting same issue with a variety of different URLs and Card types