Someone can't access the embedded form

i embedded the link to my form in an email and one person says they can't access it. Is there something I can tell them to do, or a phone number they can call for direct help from jotform?

Can you let us know if the person received any error message? Or could you could provide a screenshot? http://www.jotform.com/answers/414264-How-to-include-screenshot-image-in-the-support-forum