- Microsoft SQL Server error code 18456 refers to a failed login attempt, which may be caused by an incorrect password entry.
- Administrators can check the details of the error in the event log to get a clear picture of the problem.
- This error can be interpreted as a mechanism to prevent unauthorized individuals from accessing the server by guessing login information.
- This usually happens when “Windows Authentication” is enabled in the Security section and SQL Server cannot recognize the user.
18456 Sql Server Authentication
Sql server error 18456 is common issue appear during login process on Microsoft SQL Server. This error can happen when you try to login with local administrator, as well as under the domain administrator and under the sa. Microsoft SQL Server login failed error can be encountered due to varied reasons. Most of the time, an error code comes up with a description that gives a hint about what has gone wrong. But I some cases the error come without any description. In this article, we’ll take a look at the typical reasons of the error 18456 appear on SQL Server during login process and show different ways to solve this error.
Sql Server 18456
If “Windows Authentication” is enabled in the security section and SQL Server cannot recognize the user for the first time, possible users may encounter SQL Server error 18456.
Sql 18456
It’s not difficult to find the cause of Microsoft SQL Server (MSSQL) login errors by following some basic troubleshooting steps.
The login failed error keeps appearing even though I entered my IP address and login information for my VPS server.
There is an authentication failure, but access to the server is blocked by a permission error.
This error occurs when you attempt to log into Microsoft SQL Server and you enter an incorrect password. Although the username is accepted, this error usually occurs. However, the error message displayed does not provide any information about the cause. For a clear picture of the problem, administrators can check the event log for details.
Login Failed For User In Sql Server
It indicates a failed login attempt caused by an incorrect password entry on Microsoft SQL Server. This error message does not specify why it occurs. Generally, it occurs regardless of whether the username is accepted. However, administrators can see more detail about the problem in the event log.
It is possible to interpret this error as preventing unauthorized individuals from accessing the server through guesswork. However, real users can face difficulties solving this error.
What causes Microsoft SQL Server ‘Error: 18456’ error message?
- Connection errors occur when usernames or passwords are incorrect.
- You might have an expired password. You might also have a disabled username.
- When the Security section is enabled and Windows Authentication is enabled, SQL Server may be unable to recognize a user when connecting to a SQL Server instance for the first time.
How to eliminate “Error: 18456” in Microsoft SQL Server?

You need to be an administrator to use SQL Server
- Type SQL Server Management Studio in the search box and click Run as administrator.
- The problem might be solved if you click Yes to continue when asked for a user account.
Enable TCP/IP in the Server Configuration Manager
- Windows should open with the SQL Server icon shown next to the year. For example, 2010 would be displayed.
- When you are prompted by UAC to accept any changes, click Yes.
- Select Settings for (database/server name) under SQL Server Network Configuration.
- Under Enabled, select ‘Yes’ from the drop-down menu by double-clicking TCP/IP on the right side of the window.
- After you accept the changes, you can use the taskbar search bar.
- Choose Run as administrator from the drop-down menu after typing Services.
- You can restart the SQL Server by selecting it from the right-click menu.
Create a new login and restart Reporting Services
- Ensure that the Security tab is expanded in Microsoft SQL Server Management Studio.
- Right-click on the Logins section after expanding it.
- Your login information should now be entered when you click New Login.
- Choose the database, and uncheck “User must change password at next login.”.
- You can now select the Public role under the Server Roles tab.
- Under User Association, click db_owner.
- After applying the changes, click on the taskbar’s search bar.
- To run the tool as an administrator, click Tools.
- Choose Restart from the left-hand menu when you find the SQL Server Reporting Service.
Frequently Asked Questions
What does error 18456 mean for Microsoft SQL Server?
The common message "Login Failed for User (Microsoft SQL Server, Error: 18456)" means that you entered invalid login information when logging into SQL Server.
How to resolve Microsoft SQL Server “Error: 18456”?
- Type SQL Server Management Studio in the search box and click Run as administrator.
- If it asks for a user account, click Yes to continue and see if that solves the problem.
What are the causes of error code: 18456?
When users first connect a SQL Server instance, they may get a SQL Server 18456 error. This usually happens when "Windows Authentication" is enabled in the Security section and SQL Server cannot recognize the user.
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