The most common causes of QuickBooks Crashes When Sending Emails include out-of-date software, damaged QuickBooks installations, or problems with email setup. Conflicts with third-party apps could possibly be the cause. This can be fixed by updating QuickBooks, checking email settings, fixing the software installation, and making sure the email client is compatible. Contact the QuickBooks support staff at 1.855.738.2784 if you run into any issues.