How to fix Error 923 on Windows Server 2025 / Windows 11

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Troubleshooting Guide: Error 923 – Database in Restricted Mode (SQL Server 2025)

Why This Error Happens

This error occurs because the database’s user access option has been explicitly set to RESTRICTED_USER, which limits connectivity strictly to the database owner (dbo) and members of the dbcreator or sysadmin fixed server roles. This configuration is typically triggered manually during maintenance (such as restoring a database or running single-user diagnostic scripts) or automatically following certain recovery operations. If your current login is mapped to a standard user role without sysadmin privileges, SQL Server will reject the connection attempt and throw Error 923.

Step-by-Step Resolution Guide

Step 1: Verify Current Database State

  • Open SQL Server Management Studio (SSMS) or Azure Data Studio and connect using an account known to have sysadmin privileges.
  • Run the following query to check the current access state of the database:
  SELECT name, user_access_desc FROM sys.databases WHERE name = 'YourDatabaseName';
  • Confirm that the user_access_desc column returns RESTRICTED_USER.

Step 2: Reset the Database Access Mode

  • Execute the ALTER DATABASE command to revert the database to multi-user mode, allowing standard logins to reconnect.
  • Run this command in a New Query window:
  ALTER DATABASE [YourDatabaseName] SET MULTI_USER;
  • If the command hangs, ensure no other blocking transactions are preventing the state change by checking sys.dm_exec_requests.

Step 3: Validate User Roles and Permissions

  • If setting the database to MULTI_USER does not resolve the access issue for specific logins, verify that the user attempting to connect is correctly mapped to the database.
  • Navigate to Security > Logins in SSMS, right-click the specific login, and select Properties.
  • Under the User Mapping tab, ensure the checkbox for the target database is selected and assign the db_owner role if standard access is required moving forward.

Step 4: Restart the SQL Server Service (If Stuck)

  • If the ALTER DATABASE command fails due to a stuck session or lingering lock from the previous maintenance window, a service restart may be required.
  • Open Services.msc on Windows Server 2025 or Windows 11.
  • Locate SQL Server (MSSQLSERVER), right-click, and select Restart.
  • Re-attempt the connection via SSMS once the service status returns to “Running.”

Alternative or Verification Steps

  • Verification: Attempt to log in using a standard, non-administrative domain account to confirm the Error 923 message no longer appears and the connection succeeds.
  • Alternative: If ALTER DATABASE fails due to active connections, use ALTER DATABASE [YourDatabaseName] SET MULTI_USER WITH ROLLBACK IMMEDIATE; to forcefully terminate blocking sessions and apply the change immediately.