How to Enable Maintenance Mode in Microsoft Dynamics 365 F&O
Maintenance mode in Dynamics 365 Finance & Operations is a special system state that allows system administrators to safely make configuration changes that could impact system functionality. For example, configuration keys (features/modules controlled via License Configuration) can only be enabled or disabled when the system is in maintenance mode. While maintenance mode is active, the system is locked down so that only administrators (or users with a special Maintenance mode role) can sign in. All other users are prevented from logging in, ensuring that changes can be made without interference. By default, maintenance mode is turned off, meaning those system-wide settings are protected during normal operation.
How it works?
Under the hood, maintenance mode in D365 F&O is controlled by a simple flag stored in the system database. This flag is stored in the SQLSYSTEMVARIABLES table under the CONFIGURATIONMODE parameter. When the flag is set to 1, the application enters maintenance mode — granting access for configuration changes and restricting end-user operations. When the flag is set to 0, the system operates in standard mode and prevents modification of protected settings. You can query or update this value directly via SQL, which is particularly useful in development or cloud-hosted environments. For Microsoft-managed Tier 2+ environments, this mode is toggled via Lifecycle Services (LCS).
Enable or Disable Maintenance Mode on Tier-2+ Environments (UAT/Sandbox/Production)
Enabling or disabling maintenance mode in Microsoft Dynamics 365 F&O Tier-2+ environments (including UAT, Sandbox, and Production) is straightforward and can be done directly from LCS. Simply open the full details of your environment in LCS, go to Maintain, and select Enable maintenance mode or Disable maintenance mode as needed.
Enable or Disable Maintenance Mode on Dev/Cloud-hosted environments
Connect to the AxDB database – Log in to the SQL Server on your development machine (for cloud-hosted dev VMs, RDP into the VM and open SQL Server Management Studio). In a new SQL query window, run the following SQL command against the AxDB database to Check Maintenance Mode Status:
VALUE = 0: Disabled (default); VALUE = 1: Enabled (maintenance mode active)
Enable Maintenance Mode:
Restart IIS/IIS Express.
Perform required tasks (e.g., enable/disable configuration keys).
Run DB synchronization.
Disable Maintenance Mode:
After completing your tasks:
Restart IIS/IIS Express.
Validate system availability and functionality.
Alright, So Here’s the Deal
Maintenance mode is a powerful tool for developers and system admins—but with great power comes great responsibility. Here’s how to use it wisely:
Plan ahead: Schedule changes during off-peak hours. Maintenance mode locks out users, so notify stakeholders and pause batch jobs or integrations if needed.
Don’t leave it on: Make your changes, test them, and disable maintenance mode right after. Prolonged use can reduce system functionality and trigger alerts.
Test after changes: Once disabled, verify that everything works as expected—especially config key changes, login, forms, reports, and batch jobs.
Be extra careful in production: Always test in UAT first. Use LCS to enable/disable maintenance mode in production and make sure you have rollback options.
Done right, maintenance mode lets you safely make important configuration changes.