When I test submit a response I get an error

I am receiving the following error when I try to test my form:

 

500 Internal Server Error nginx/1.9.3

My apologies, we had a minor attack on our severs that has been mitigated.  Everything should be back up once again.  If you have any further issues with the 500 error, let us know and we will be happy to have a look at your forms.