Common SQL Server Errors and their Solutions – A Comprehensive Guide

MS SQL Server is one of the widely used relational database management systems (RDBMS). It is used by more than 182,000 companies across the globe, majority located in the United States, according to a report by enlyft. The top industries using SQL Server are Information Technology and Services (20%) and Computer Software (12%).

MS SQL Server provides a comprehensive set of tools to store, manage and retrieve data. These tools requires to connect to a SQL server instance, which is running service of the database engine acts as a core component of Server. A single system can have multiple instances, and each instance can have one or more databases. Each database organizes data into schemas and objects such as tables, views, and procedures.

A database in MS SQL Server contains a collection of tables that stores a specific set of structured data. A table contains a collection of rows (also referred to as records) and columns (also called attributes). Each column in the table is designed to store a specific type of information, such as dates, names, numbers, etc.

Though MS SQL Server is a reliable database management system, users at times encounter random errors while performing routine operations, such as executing queries, creating database backup, restoring backup, etc. These errors can result in database unavailability, adversely impacting the projects timelines and business workflow.

In this comprehensive guide, we will be explaining the common SQL Server errors and how to effectively handle and resolve them.

Understanding SQL Server Errors

The errors you encounter in SQL Server are messages that indicate problems occurred during the execution of queries or other operations. These errors can be simple syntax errors or related to complex problems, such as connection failure, server failure/crash, or database corruption. Every error message is accompanied by a particular error code that helps ascertain the nature of problem and implement the right solution to resolve it.

Depending on the nature of problem and issue, we will be categorizing the errors under four broad categories:

A. Database Corruption and Consistency Errors

B. Restore, Backup, and Log Errors

C. Attach/Detach and File-Level Errors

D. General Database errors-Access, Permission, Login, Startup, Service & Configuration Errors

Let’s go through the common SQL Server errors and see how to troubleshoot them.

Common SQL Server Errors and their Solutions

Here is a list of errors you may encounter in SQL Server, along with the solutions.

A. Database Corruption and Consistency Errors 

SQL Server manages and stores all the data in database files, which consists of tables, indexes, stored procedures, views and other objects. Such database files are stored on your system disk as primary data files i.e. MDF, secondary data files (.NDF), transaction log files. Like other files, these database files are prone to corruption, integrity, and consistencies issues. Such issues often occur due to various software and hardware issues, sudden application and system failure, and disk issues.

If any of these files get corrupted, damaged or unreadable, it can lead to consistency errors in SQL Server. The consistency issues usually occurs if data pages, indexes, or checksums in database get corrupted. You can check the database corruption in SQL server using PAGE VERIFY option, DBCC CHECKDB command, Error Logs, etc.  Listed below are some errors related to database corruption and consistency issues.

SQL Server Error 823

The DBCC CHECKDB usually reports this error if it detects inconsistencies in the Database file. This error is commonly associated with database structure issues, such as torn pages or incorrect Page IDs. Another variant of 823 error is cyclic redundancy check (CRC) error, which often occurs when there is a physical corruption in the file system or disk hardware. You can check thorough details about both errors in the ERRORLOG and Windows Event Log.

Solutions to Fix the SQL Error 823:

You can first try to restore the database file from backup. If the error persists or backup is not available, then repair the database using the DBCC CHECKDB command or a professional SQL repair tool. For detailed step-by-step process to fix this error, refer to this blog.  

SQL Server Error 825

This inconsistency error is a read retry I/O warning where disk reads fail initially but succeed after retries. It means that there are some problems with the system’s disk or storage that can impact database integrity.

Solutions to Fix the SQL Error 825:

To resolve the 825 error and prevent further corruption in the database, you can check disk health, update drivers, or move the SQL database file to a new physical drive. As we know this error can threaten the database integrity, if there are integrity issues then you can run DBCC CHECKDB, or use any professional SQL repair tool.

SQL Database Error 824

This error is more identical to the error 823 as it is reported by DBCC CHECKDB command. It occurs when the SQL discovered some issue with the page in the database.

Solution to resolve SQL error 824

To troubleshoot SQL database error 824, you can check the health of your system file system and storage devices, restore or repair SQL database file using backup or using DBCC CHECKDB repair options.

SQL Server Database error 829

Usually, you see this database integrity error reported by DBCC CHECKDB command error when the automatic page repair occurs in Database Mirroring or Always On Availability groups.  It happens when corruption in Database or I/O errors are detected. This error marks database page as restore pending state, makes the database temporarily unreadable and impacts the mirroring/replication process.

In Always in availability groups, you should first check if the corruption in database is isolated to single replica, remove it from AG group then repair corrupt SQL database in always in availability groups.

Solutions to resolve SQL error 829:

You can resolve the database error 829 by restore the database from backup or repair the database using the DBCC CHECKDB command.

SQL server error 832:

This error is one of the logical consistency based I/O errors usually returned by DBCC CHECKDB command when it detects issue in database pages. The page issue can occur by an external DLLs used in SQL server, outside the database engine. Also, happens if the thread running in the SQL server processes the incorrect writes on a database page. The error message looks like

Solutions to resolve SQL error 832:

To resolve the 832 error, first check the error details in your system’s Event Viewer or SQL server Error logs. Next, check whether external DLLs, stored procedures that might be interfering with SQL servers and remove them. To check the DLLs related to SQL server run the sys.dm_os_loaded_modules command:

SELECT *

FROM sys.dm_os_loaded_modules

ORDER BY base_address;

MSSQL error 8930

The Primary data file also known as MDF file stores the metadata of the database objects like table names, indexes, schemas, etc. If the metadata in MDF file becomes corrupted or inaccessible then you can face inconsistencies errors like 8930, 8966, 8967, 8967, 8930. The error message looks like:

Solutions to resolve SQL error 8930:

To resolve the error 8930 and such errors you can rely on a professional SQL repair tool to repair the MDF file.

SQL server error 8966

Error 8966 in SQL server usually occurs if Server fails to get the latches or if there is corruption in buffer pools, pages, data pages, indexes, latch pages, etc. in the SQL database.

Solutions to resolve SQL error 8966

To resolve this error, you can remove the latch contention or fix the page corruption in SQL server. In case you know the specific page number in the error message or in error log then use PAGE RESTORE method. If the multiple pages or corrupted then use DBCC CHECKDB command to repair the pages in SQL database.

SQL database error 3624 a system assertion check has failed

SQL server uses the Asserts statements in some places to ensure the certain conditions are satisfied or not. If it fails to read the Asserts, due to the physical and structural corruption in database, or software bugs, or external library or filter driver, can result in system assertion check fails.

Solutions to resolve SQL error 3624

To resolve the SQL database error 3624 a system assertion check has failed, you can check the external modules loaded in SQL server memory space and drivers using the following commands:

SELECT * FROM sys.dm_os_loaded_modules

WHERE company != 'Microsoft Corporation'

For filter drivers, open the CMD window on your system and run the following command:

Bash

fltmc filters

Once completed, initiate SQL database recovery at the earliest if the system assertion check fails due to database corruption.

SQL server error: Incorrect PFS free space information error

The “Incorrect PFS free space information" error is also one of the corruption and inconsistency errors in SQL server. It usually occurs when the server database engine fails to read the information stored in the PFS (Page free space) pages. The error itself displays the problematic object name, table name, object ID, Partition ID, and Page ID and repair option.

Solutions to resolve “Incorrect PFS free space information" error

To repair this error, follow the recommended DBCC CHECKDB repair option or assign new data pages and PFS entries by copying the data from the source table to a new table. To know the complete troubleshooting guide read this blog.

SQL Database in Suspect mode

One of the common scenarios of SQL database corruption is your database enters suspect mode. It happens when you connect the database in SSMS, the SQL server engine fails to complete database recovery at startup. It usually happens when the database is severely corrupted or transaction log file is missing.

Solution to resolve SQL database in Suspect mode issue

You can recover the database from suspect mode by running the DBCC CHECKDB command after accessing the database in an Emergency mode. To recover highly corrupted MDF/NDF files from suspect mode, opt for a professional SQL repair tool.

B. Restore and Backup Errors

Creating a backup file protects data, ensures data integrity, and minimizes downtime. A backup (.bak) comes in handy when the database becomes inaccessible or gets corrupted. If you have a healthy, and readable recent backup of your backup file, then you can easily restore the backup in case of any issue with the database.

 

SQL server offers reliable methods to create backup and restore database in MSSQL. Still, errors may occur while during these operations. Issues can arise when creating or restoring any type of backups like full, differential, or log backups. Frequent backup errors in SQL Server include:

SQL Server backup error 3183

This error occurs when you try to restore database from backup file. Its error message displays level 16 which means it is a severe error which occurs when page validation fails due to the corruption in the database or backup file.

 

Solutions to resolve SQL error 3183

 

As an administrator you should first verify backup integrity with RESTORE VERIFYONLY. If corruption is found, then try to restore the backup using CONTINUE_AFTER_ERROR or rely on specialized SQL repair tools to repair SQL server error 3183.

SQL Server Error 3013

This error appears when the backup process or restore process is terminated abnormally. It happens when the corruption in database, file mark issues on the device or incorrect path to the backup storage device make the server fails to read the backup file.

Solutions to resolve SQL error 3013

 

To resolve backup/restore error 3013 in SQL, you can check and grant the permissions of the backup file and check the integrity of the backup file. If the backup file is corrupted then you can repair the file using Stellar Repair for MS SQL.

SQL Database error Restore Failed, Database in Use

This error indicates that the backup file you want restore is already in use or has some issues.

Solutions to resolve SQL issue: database restore failed, Database in Use

You can check and restart the services and disconnect all existing connections. If the corrupt backup file is behind the issue, then you can repair it to resolve the SQL database restore failed error.

SQL Server Database Restore Error 5243

The lack of space on the disk storing the backup file and the corruption in the backup file can trigger the server to throw the restore failed errors.

Solutions to resolve SQL error 5243

You can check the storage space on your system hard disk or repair the backup (.bak) file to fix the error 5243 in SQL server.

SQL Server Database Error 3241: Restore Header only

This error can appear if you try to restore the backup file, created in a higher version of SQL Server, in an earlier version of SQL Server or corruption in backup file.

Solutions to resolve SQL error 3241

 You can check the version of backup file to resolve the SQL database error 3241: Restore   Header only error.

SQL Server error database Cannot Be Recovered Because the Log Was Not Restored

This error occurs when SQL Server fails to complete database recovery due to the missing transaction log files. It happens if you follow the restore sequences incorrectly. When you encounter this situation, the database usually stuck in the restoring state.

Solution to resolve error “The Database Cannot Be Recovered Because the Log Was Not Restored”

To resolve it, make sure you restore all the log backups in order or try to detach the database. You can follow this guide to know more about this error.

SQL Error 3201: Cannot Open Backup Device

This error occurs when the SQL server fails to access the backup file or backup device. This can happen due to locked files, incorrect backup paths, file permission issues or corruption in Backup file.

Solutions to resolve SQL error 3201

Resolving this error requires checking and granting the file permissions and ensuring the backup paths are correct. If the backup restore fails due to corruption in backup file, then you can resolve the error 3201 using a professional SQL repair tool as no native backup repair tool is available.

SQL server error 3156: Database cannot be restored

You can face this error while restoring the backup file in SQL server. It occurs when the database you’re trying to restore has a memory-optimised filegroup. It usually appears when backup file paths are incorrect or there is already a folder with the same name in the same folder path, and the folder is already in use by SQL Server or other processes.

Solutions to fix SQL error 3156

To resolve the error 3156, you can

• Use a different folder name or a different folder path when restoring a database using GUI

• Specify a new location for the files using the WITH MOVE option in restore statement.

SQL server error 3154

Error 3154 occurs when restoring a backup over an existing database without WITH REPLACE. It indicate issues with the .bak or original database file.

Solutions to resolve SQL error 3154

Use RESTORE ... WITH VERIFYONLY to check backup integrity; if corruption is found, repair the file before retrying. You can check this troubleshooting guide to resolve error 3154

SQL server error 15105

It is also one of the backup errors in SQL server that usually occurs when you try to create a .bak file on network share. Common causes include

• Network conflicts

• Insufficient permissions

• lack of disk space

• Corrupted backup files.

Solutions to fix error 15105

To resolve the error 15105, check SQL Server error logs to identify the issue and accordingly apply the fix.

C: Attach/Detach Errors

SQL server provides you options of detaching and attaching a SQL server database. Attaching means simply reconnecting the existing database files to your Server instance and detaching means separating your database.  With these features you can move databases files in the file system and to a new server as well. To move a database to a different Server instance, you require to detach the database, move the database files to the server and then attach the files.

While attaching the SQL database like MDF file, you also require the transaction log file, along with it. If the transaction log file, or MDF file are missing, corrupted, damaged or unreadable due to any reason, you may encounter attaching and detaching errors. In this section, you will learn common attaching/detaching errors due to corrupt Log file and MDF file:

SQL Server error 5171/5172

You may encounter the attaching errors like 5171/5172 if the transaction log file or MDF file is corrupted or missing.

Solutions to fix error 5171/5172

To resolve these errors , you can rebuild the transaction log file by attaching the database without the transaction log file. You can check and configure file system permissions for database engine access.  If the corrupt header of the MDF file is behind the error then you can repair MDF file using the DBCC CHECKDB command.

SQL Server error 9002

The error 9002 occurs when attaching the database or restoring the SQL database from backup file. It occurs when the transaction log becomes full, the Autogrowth option is disabled, a long running transactions, and more.

Solutions to fix SQL error 9002

To resolve the error 9002, you can follow the troubleshooting steps like

• Recreate the transaction log file

• Change the log file growth settings

• Shrink the Transaction log file

• Check and enable Autogrowth option for the log file.

SQL Server error 5173- attach database failed

You may encounter error 5173 while attaching the SQL database file. It occurs when the primary data file (.MDF) and log file (.LDF) mismatches or they are corrupted.

Solutions to resolve SQL error 5173

To resolve the attach database failed error 5173, you can use FOR ATTACH_REBUILD_LOG or  repair the MDF file with specialized SQL repair tool like Stellar Repair for MS SQL.

SQL Server Error 9003

It is one of the database attaching errors that often occurs when the SQL database file or transaction log file are corrupted.

Solutions to resolve SQL error 9003

As a quick solution, you can try attaching the database without transaction log file using the below T-SQL statements.

CREATE DATABASE testdb ON

(FILENAME = ‘C:\Program Files\Microsoft SQL Server..\MSSQL\DATA\testdb5.mdf’)

For ATTACH_REBUILD_LOG

GO

Or follow this troubleshooting guide to fix SQL attach database 9003 error.

SQL Server 9004

The SQL Server error 9004 is related to a problem with the transaction logs. If the log file header or the Virtual Log File (VLF) is damaged or corrupted due to hardware failure, unexpected server shutdown, etc.

Solutions to resolve SQL error 9004

To resolve the 9004 error, you can rebuild the transaction log file using the below command.

USE [master]GOCREATE DATABASE [AdventureWorks2019] ON( FILENAME = N'c:\data\adventureworks2019.mdf' )FOR ATTACH_REBUILD_LOGGO

Otherwise, you can restore transaction log backup file to restore the transaction log file. While restoring the backup make sure it is restored in the order in the same order in which they are created.

SQL Server error: Attach Database Failed Error 1813

Error 1813 also belongs to the database attaching errors. The complete error message reads as:

Error Msg 1813, Level 16, State 2, Line 1

Could not open new database ‘Database_Name’. CREATE DATABASE is aborted.

It occurs when you try to attach the MDF file and you don’t have all permissions to access the file, if the log file is corrupted or the MDF file itself is corrupted.

Solutions to resolve SQL error 1813

You can rebuild the log file, or repair the SQL database to resolve the error 1813 in SQL server.

D: General Database Errors

There are specific list of SQL database errors that are not limited to backup, restore or attach/detach operations. Such errors can happen at any time, while working on SQL. These general database errors you may encounter due to Access, authentication failures or permissions issues. These can prevent you from connecting to or working with the database. These includes:

SQL Server Error: Operating system error 5 access is denied

The error “Operating system error 5: Access is denied” in SQL Server often occurs due to lack of permissions, your SQL Server database engine service account does not have permissions to read/write backup folder, etc.

Solutions to resolve Operating system error 5 access is denied in MS SQL server

You can check the file and folder path while restoring the backup, check and provide the right permissions to fix error 5 error in SQL server.

SQL Server Database Error 18456

This error is one of the login‑failed errors in SQL Server. It usually occurs when there are authentication failures, incorrect login and password.

Solutions to resolve SQL error 18456

You can check the logins by locating the Security section and then clicking Logins in SSMS. Check and enable SQL Authentication to resolve the error 18456. In case you fail to recover and reset lost passwords for the SQL Server database, then you can use a SQL password recovery tool.

SQL database error cannot open user default database

The SQL Server error “Cannot open user default database. Login failed” (Error 4064) occurs when SQL fails to connect to the default database while login. It occurs when there is some issue with the user’s database, it is unavailable, deleted, or offline, the login does not have proper permissions.

Solutions to fix SQL Server error 4064

To resolve the SQL database error cannot open user default database, try the following solutions:

• Restoring or re-attach the problematic database

• Connect database using another database such as master, then change the login’s default database in your SSMS.

SQL Server Database Error 945

This error can occur when the server fails to access the system databases or logins. It prevents you from opening the database, attaching a SQL database, or restoring the backup file. It can occur due to disabled Auto-grow feature, SSISDB upgrade conflicts, lack of permissions to update files in SQL service account, damaged MDF/LDF/BAK files, etc.

Solutions to resolve error 945

You can check and grant file permissions, fix SSISDB upgrade conflicts, or repair database files to resolve SQL error 945.

SQL Server error 3417

You may encounter error 3417 while connecting to the SQL server instance in SSMS. It occurs

• When the server fails to upload the master database due to issue with the Upgrade scripts

• Folder permission issues where the database is saved

• Damaged or compressed MDF/NDF file

• Changes in Windows settings.

Solutions to fix error 3417

You can resolve the SQL server error 3417 by decompressing the MDF file, Checking and granting Folder Permissions. If the issues in master database is behind the error then restore the master database from the backup.

SQL Server error 1067

The Error 1067 occurs when you start, or restart SQL Server or SQL Server Agent fails. It usually takes place due to corrupted system or database files, insufficient permissions, or TCP port conflicts.

Solutions to fix error 1067

You can check and change SQL server port to resolve TCP port conflicts, and file permissions, to resolve the Error 1067: The process terminated unexpectedly.

SQL Server 2008 r2 error 926

You may encounter this error while working on SQL server 2008. It occurs when the database recovery failed due to a torn page, I/O error, or any hardware issue.

Solutions to resolve SQL error 926

You can restore the corrupt database by restoring the backup file or use repair options of DBCC CHECKDB to fix the error 926 in SQL server.

Best Practices to Prevent SQL Server Errors and Database Corruption

You can proactively follow the following preventive strategies to prevent corruption in SQL database and its related errors. Some of them are below:

Ensure you’ve corruption-free backup file

Before restoring the backup file, make sure it is free of corruption. For this you can check the integrity of the backup file using the command like RESTORE VERIFYONLY. As, the SQL server doesnot provide native tools to repair backup file, so it is best practice to keep a reliable third-party backup repair tool handy with you. So that, if integrity issues are detected, it helps you quickly repair and restore the backup file.

Regularly Update and Patch the Server

Keep your SQL server up-to-date by installing the latest patches and updates (as and when available).

Check and Grant All Permissions

Before proceeding to restore and attach SQL database make sure, you have the membership of the db_owner fixed database role and these permissions:

• CREATE DATABASE

• CREATE ANY DATABASE

• ALTER ANY DATABASE permissions

Perform Regular Backups

Make sure you perform regular backups of your SQL database. You can even schedule this process weekly. To create backup, make sure you have

• All permissions (BACKUP DATABASE and BACKUP LOG permissions) to members of the sysadmin server role, the db_owner and db_backupoperator to backup roles.

• The SQL server service must have read and write permissions to the backup drive

• Enabled checksums so that server validates pages during the backup process

Monitor logs

Regularly review your SQL Server and Windows Event Logs for early errors and warning signs

Perform Integrity Checks

You can check SQL database for corruption proactively using the DBCC CHECKDB command. This helps you catch the corruption in SQL database before it further spreads or cause major data loss.

Conclusion & the way forward

Encountering errors is inescapable when managing databases and performing operations on SQL server. However, carrying a strong analytic and technical skills and applying a structured, and research-oriented error analysis approach, you can effectively detect, troubleshoot and resolve issues.

This ensures the database availability and minimizes downtime. This keeps SQL server processes and operations running smoothly. By understanding common errors, applying best practices, and proactively detecting issues, you can maintain data integrity and optimize performance.

This post discussed some common SQL database issues and the fixes to resolve them. This helps you easily and quickly use your analytical skills to approach the error with confidence.

Usually, database errors occur due to inconsistencies or corruption in the database (MDF/NDF) or backup file. You can use DBCC CHECKDB tool and the ‘RESTORE VERIFYONLY’ command to identify if the SQL database or backup is corrupted. To resolve the database files quickly, with no data loss, the best method to Stellar Repair for MS SQL Technician. It not only repairs the MDF/NDF file but also, repair severely corrupted .bak file created with any backup type like full, differential, and transaction log backups. The tool can repair database file of SQL Server 2022, 2019 and lower versions.