I have 3 sites using the same main List -- all 3 have ceased working properly since updating to the latest version of WordPress, 3.4.1. I have removed the Widget from the sidebars, re-entered the API Key, edited the Widget slightly to give it new content to render, etc. -- to no avail.
The site (multi-site) setup is via: http://miadventureracing.com/ -- there are 3 sites linked to from that homepage:
Each of the sites' signup form renders the default error message upon attempting to signup now: "There was a problem processing your submission."
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