add troubleshoot server section

windows/threat-protection/windows-defender-atp/troubleshoot-onboarding-windows-defender-advanced-threat-protection.md

@@ -265,6 +265,23 @@ If the verification fails and your environment is using a proxy to connect to th
 
     ![Image of registry key for Windows Defender Antivirus](images/atp-disableantispyware-regkey.png)
 
+
+## Troubleshoot onboarding issues on a server
+If you encounter issues while onboarding a server, go through the following verification steps to address possible issues.
+
+- Ensure that you have followed the guidance in the topic [Configure server endpoints](configure-server-endpoints-windows-defender-advanced-threat-protection.md) and have you've configured the necessary server endpoint proxy and Internet connectivity settings.
+
+- Check that there is a Windows Defender Advanced Threat Protection Service running in the **Processes** tab in **Task Manager**. For example:
+
+    ![Image of process view with Windows Defender Advanced Threat Protection Service running](images/atp-task-manager.png)
+
+- In **Event Viewer**, check **Event Viewer** > **Applications and Services Logs** > **Operation Manager** to see if there are any errors.
+
+- Check if the **Microsoft Monitoring Agent** is running on the server. 
+- Check to see that machines are reflected in the **Machines list** in the portal. 
+
+- [Run a detection test](run-detection-test-windows-defender-advanced-threat-protection.md) on the server.
+
 ## Licensing requirements
 Windows Defender Advanced Threat Protection requires one of the following Microsoft Volume Licensing offers: