The Salesforce Technology team have resolved a service disruption impacting all Pardot account users "Login With Salesforce" feature and the creation of Salesforce Connectors between 9:36 pm, 5 September 2018 to 1:21 am, 6 September 2018 UTC. Full services have been restored.
During this service disruption, end users were unable to access the Pardot service using "Login with Salesforce" or create Salesforce Connectors within Pardot.
Please contact Support at http://success.pardot.com
if you encounter any further issues. We sincerely regret any inconvenience you have experienced as a result of this incident.