I ran into this exact error.
As I am just doing some development with Neo4j -- no production side things yet I haven't been using https/ssl. I didn't realize that the v3.5 neo4j.conf file that I brought over from my v3.5 server to the v4.0 server had dbms.connector.https.enabled=true set. I'm assuming you checked this, but I didn't and commenting it out solved my problem immediately.
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