QuickBooks outlook is not responding error usually arises when the user tries to send an email using outlook as the primary email client. Generally, the error occurs because of compatibility issues between QuickBooks and Outlook. Sometimes, restarting outlook and running both QuickBooks and Outlook as an administrator can fix the error. For quick assistance to resolve QuickBooks outlook is not responding error, dial our toll-free number (1.800.579.0391) and talk to certified QuickBooks professionals.All Rights Reserved