Dataverse Connection Errors
If the 'Test Connection' button fails when configuring your Dataverse source, check the following:
| Error / Symptom | Solution |
| Invalid URL format | Ensure the Base URL follows the pattern: https://yourorg.crm.dynamics.com (no trailing slash). Check for typos and verify the correct regional domain (crm.dynamics.com, crm4.dynamics.com, etc.). |
| 401 Unauthorized | The Client ID or Client Secret is incorrect. Verify both values match your App Registration in Azure Portal. Check that the secret hasn't expired. |
| 403 Forbidden | The Application User exists but lacks permissions. Review the security roles assigned to the Application User in Dataverse and ensure it has read access to the tables you want to synchronize. |
| 404 Not Found | The environment URL is incorrect or the environment doesn't exist. Verify the URL in Power Platform Admin Center. |
| Application User not found | Create an Application User in Dataverse linked to your App Registration. Navigate to Power Platform Admin Center → Environments → Settings → Application Users. |
Azure SQL Connection Errors
If the 'Test Connection' button fails when configuring your Azure SQL target, check the following:
| Error / Symptom | Solution |
| Cannot connect to server | Verify the server address format: yourserver.database.windows.net. Ensure there are no typos. Check that the server exists in Azure Portal. |
| Firewall blocking connection | Add the Data Mission Sync static IP address to your Azure SQL firewall rules. The IP is shown in the profile wizard when you select your region. |
| Database does not exist | Verify the database name exactly matches what's in Azure Portal. Database names are case-sensitive. |
| Login failed for user | The App Registration hasn't been granted access. Run CREATE USER and ALTER ROLE commands in your database. See Configuration & Prerequisites. |
| Request failed with status code 504 | Your Serverless database is auto-paused. Wait a few seconds and click 'Test Connection' again. See Azure SQL Auto-Pause below. |
Azure SQL Auto-Pause (Serverless)
If your Azure SQL database uses the Serverless compute tier, it may auto-pause after a period of inactivity to reduce costs. When this happens:
• First connection attempt: You may see 'Request failed with status code 504' or a timeout error
• The database is waking up from a paused state (this typically takes 10-30 seconds)
• Solution: Wait a few seconds and click 'Test Connection' again — the connection should succeed
During scheduled synchronizations, Data Mission Sync automatically retries connections to handle auto-paused databases. However, for optimal performance, consider:
• Setting a minimum auto-pause delay in Azure (e.g., 1 hour instead of the default)
• Using a Provisioned compute tier for production workloads with frequent syncs
• Scheduling syncs frequently enough to keep the database active (hourly syncs typically prevent auto-pause)
• Configuring Quiet Time periods in Data Mission Sync to align with your auto-pause schedule — this allows the database to pause during off-hours while ensuring syncs run when the database is active
| 💡 Tip: If you're using Serverless to save costs, configure Quiet Time periods (e.g., overnight) to let the database auto-pause. Syncs will run outside quiet time when the database is active, maximizing your cost savings while maintaining data freshness. |