MS SQL Server 18456 Error | How to Fix It Fast

Prominent Causes of Microsoft SQL 18456 Error

SQL Server Error 18456 login failed sa can arise for any of the following reasons:

• Providing incorrect login credentials for SQL Server account.
• Disabling accounts intentionally or due to system configuration changes.
• Improper configuration of authentication mode for the SQL Server.
• Corrupted SQL database or MDF/NDF/LDF files and system tables.
• Also, insufficient permissions by DBAs result in login failures.
• Server misconfiguration, network problems, or antivirus and firewall issues block login attempts.

Responses of the Error 18456 in SQL

• Failed to open a directly specified database in the SQL Server.
• Issues related to user authentication preventing their access.
• Disrupts SQL application functionality, resulting in file corruption.

How to Resolve Windows SQL Server 18456 Error?

Several troubleshooting methods are available to resolve the 18456 login error. These methods can range from manual fixes to advanced troubleshooting methods. Below are the available manual techniques and a professional tool to resolve this issue.

Manual Method to Resolve Error 18456 in SQL Server

Follow these three steps to manually fix error 18456 in the Windows SQL Server:

Step 1: Check Connection for SQL Server

1. Start SSMS, i.e., SQL Server Management Studio, and connect to the problematic database instance.
2. Then, right-click it and choose the Properties option from the list.
3. In the open window, navigate to the Security page and check the authentication section.
4. There, ensure that the radio option for SQL Server and Windows Authentication mode is chosen.
5. If not, and the authentication mode is set to Windows, change it and press OK to save changes.
6. Finally, restart the SQL Server and check if the error 18456 in SQL Server is resolved.

Step 2: Check Authorization for SQL User Account

1. First, connect to the SQL server database instance in SSMS.
2. Then, expand the Security tab and choose Login from the given options.
3. See whether the login account related to the SQL Server 18456 error is listed or not.
4. If it is listed, right-click it and select the Properties option.
5. After that, verify that the user login is enabled and has the necessary rights.
6. Additionally, see if the user is assigned the correct roles in the SQL Server.
7. If needed, enable the login from the Status tab and assign appropriate roles.

Step 3: Verify SQL Logs in the Server

Server Logs provide detailed information on failed login attempts by the user in SQL Server.

1. In SSMS, right-click the database instance and navigate to Management.
2. There, click View SQL Server Logs and look for entries like 18456 login failed for the user in the logs.
3. If you encounter 18456 with any state like 1, 5, etc., use it to determine the main cause.

In the end, some other basic troubleshooting that you can do for the Microsoft SQL 18456 error are:

• Check the login credentials and database activeness.
• Verify its status is Online. If not, then restore it from a backup.
• Recover SQL database from damage or corruption.

Shortcomings of the Manual Method

• It is a lengthy process and involves many steps to ensure the error is resolved.
• No guarantee of the elimination of this SQL login error.
• Users must have SQL knowledge or good technical help.
• These troubleshooting solutions provide no security for the database.

Professional Approach to Resolve SQL Server 18456 Issues

When manual ways do not resolve errors, use the SysInfo SQL Database Recovery Tool. It is built to handle the issues related to SQL files and databases. The tool can recover the corrupted database files and restore the data in a new database or as scripts. Additionally, it recovers all the SQL objects, including tables, procedures, rules, and more. Moreover, the tool has an easy GUI that any techie or non-techie user can run smoothly. It also has some versatile features, such as:

• Offers two recovery solutions for repairing the damaged data.
• Supports all the new and old SQL Server and Windows OS versions.
• Keeps the data intact and displays a preview of the recovered data.
• It can handle single as well as multiple files without any complexity.
• Provides selective filters to restore specific parts of the database.

Steps to Fix SQL Server 18456 and Recover Data

1. Download the SQL Database Repair Tool and install it as an administrator.
2. Press Open and select the database MDF file from the system to add.
3. Further, select the Standard or Advanced recovery and other choices. Click OK.
4. Preview the recovered data from the tree format in the panel and select tables.
5. Afterward, press Save SQL Data and choose either the Database or Scripts option.
6. At last, select the filters needed and click the OK button to recover completely.

Conclusion

To sum up, error 18456 can be frustrating for both DBAs and users. However, it is not impossible to overcome. Understanding it and applying appropriate methods are key to troubleshooting and recovery. It will minimize downtime and maintain a smooth SQL Server environment. If manual solutions don’t work to fix the SQL Server 18456 error, using a professional tool can save the day.

Frequently Asked Questions

About The Author:

Lovely Baghel

Lovely specializes in technical writing for SysInfoTools Software and has over 2 year of experience writing blogs, and articles about databases & backup, email recovery, email migration & management solutions. Her passion is researching and developing content that helps Office users, professionals, administrators, enterprises, and novices solve multiple problems.