Solved – 0×80070057 Error Outlook 2010 Posted on August 25, 2017August 25, 2017 by dpejic 0×80070057 Error Outlook 2010 This is a quite common error on Outlook 2010 x64. Error Code: An unknown error occurred, error code: 0×80070057 Symptom: It occurs when you try to add a new Exchange account in Outlook 2010 And in most cases because you try to use the AutoAccountSetup to create the newaccount Solution: For me, solution was to turn off proxy settings or to add exeption for autodiscover address