Works, but displays error message

Hi – first of all, thanks for the plugin.

I have configured the widget with all the correct information and keys and added it to my website. When I proceed to test it, I get an error message:

Sorry, we weren’t able to sign you up. Please check your details, and try again.

However, when I check my list in Campaign Monitor, the email has been added successfully. I have tried this several times now, with different lists and keys, but the result is the same.

I have tried following the steps you recommended here http://www.leewillis.co.uk/debugging-problems-campaign-monitor-widgets/ but I get no error at all.

Any idea of what the problem might be?

Thanks in advance.

http://wordpress.org/extend/plugins/ajax-campaign-monitor-forms/