The Email Delivery Troubleshooting tool helps you identify and solve problems that affect the delivery of email to or from your organization. The tool can also help reduce the level of spam your organization receives. You provide simple information about the problem you are experiencing, and the tool displays steps you can take to solve the problem. The tool also provides detailed results of all of the individual checks it performed. You can choose to have the tool's results displayed on the screen, or emailed to you or other users.
You can find Email Delivery Troubleshooting in the portal under the Tools tab.