When Vuture is unable to connect to your CRM at the point of selecting a list in the Send Email Screen, you are notified through an error message:

"We are unable to load any CRM lists. Please contact your administrator or Vuture Support"

This text can be edited, for example to include how to contact your CRM team.  

Please contact your Account Manager if you would like to modify the message which they can do using the configuration setting:  "Admin.System.Emails.No connectivity to CRM error message".