Endnote is unavailable

Hi, I keep getting the error message… ‘’ EndNote is unavailable. Please verify that the EndNote URL is correct and try again.’’ 

I don’t know why this message keeps being displayed, I have used endnote for a few years now with no problems. With deadlines fast approaching I am concerned that I might have to abandon using the software.

Thank you for any advice you can offer. 

screen shot?  From word processor?  from the program?  which version – web or desktop.  need a few details.