"Microsoft Office has identified a potential security concern" in Onenote2013

Hi

I work with outlook 2013. I creat a meeting and share it with Onenote. then I send meeting to attendees.

attendees receive meeting. when they click "View meeting notes(web)" link; they see this Error: "Microsoft Office has identified security cocern"

what shoud i do??

when i click yes: onenote asks me to sign in; if no: meeting open in onenote but  there isn't all of chenges that  i had done in original onenote file.

what should i do if  my attendees want to see meetings in onenote file with all of the chenges in original file? 

Thanks for your help!