This step-by-step article discusses the steps you can use
to change the SQL Server sa
(system administrator) password.
You can configure
Microsoft SQL Server 2005 Express, Microsoft SQL Server Desktop Engine (MSDE) versions 2000, or earlier versions of Microsoft SQL Server to run in
Mixed Authentication mode. The sa
account is created during the installation process and the sa
account has full rights in the SQL Server environment. By
default, the sa
password is blank (NULL), unless you change the password when you
run the MSDE Setup program. To conform with the best security practices, you
must change the sa
password to a strong password at the first
How to verify if the SA password is blank
- On the computer that is hosting the instance of MSDE to
which you are connecting, open a command prompt window.
- At the command prompt, type the following command, and
then press ENTER:
osql -U sa
connects you to the local, default instance of MSDE by using the sa account. To connect to a named instance installed on your
osql -U sa -S servername\instancename
You are now at the following
- Press ENTER again. This will pass a NULL (blank) password
If you are now at the following prompt, after you
press ENTER, then you do not have a password for the sa account:
We recommend that you create a non-NULL, strong password to conform
with security practices.
However, if you receive the following error
message, you have entered an incorrect password. This error message indicates
that a password has been created for the sa account:
The following error message indicates that the computer that is
running SQL Server is set to Windows Authentication only:
"Login Failed for user 'sa'."
You cannot verify your sa password while in Windows Authentication mode. However, you can
create a sa password so that your sa account is secure in case your authentication mode is changed to
Mixed Mode in the future.
Login failed for user 'sa'. Reason: Not associated with a trusted
SQL Server connection.
If you receive the following error message,
SQL Server may not be running or you may have provided an incorrect name for
the named instance of SQL Server that is installed:
[Shared Memory]SQL Server does not exist or access denied.
How to change your SA password
- On the computer that is hosting the instance of MSDE to
which you are connecting, open the command prompt window.
- Type the following command, and then press
osql -U sa
At the Password: prompt, press ENTER if your password is blank or type the current
password. This connects you to the local, default instance of MSDE by using the
sa account. To connect by using Windows authentication, type this
command: use osql -E
Note If you are using SQL Server 2005 Express, avoid using the Osql utility, and plan to modify applications that currently use the Osql feature. Use the Sqlcmd utility instead.
For more information about the Sqlcmd utility, visit the following Microsoft Developer Network (MSDN) Web site:
- Type the following commands, on separate lines, and then
Note Make sure that you replace "complexpwd" with the new strong
password. A strong password includes alpha-numeric and special characters, and
a combination of upper and lower case characters.
sp_password @old = null, @new = 'complexpwd', @loginame ='sa'
You will receive
the following informational message, which indicates that your password was
How to determine or change your authentication modeImportant
This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click the following article number to view the article in the Microsoft Knowledge Base:
How to back up and restore the registry in Windows
If you are not sure how to verify the
authentication mode of your MSDE installation, you can check the corresponding
registry entry. By default, the value of the Windows LoginMode
registry subkey is set to 1 for Windows Authentication. When
Mixed Mode authentication is enabled, this value is a 2.Note
Before you switch authentication modes, you must set a sa
password to avoid exposing a potential security hole.
To switch from Mixed Mode to Integrated (Windows)
authentication, follow these steps:
- To stop MSSQLSERVER and all other related services (such as
SQLSERVERAgent), open the Services applet in Control Panel.
- Open the Registry Editor. To open the Registry Editor,
click Start, click Run, and then type: "regedt32" (without the quotation
- Locate either of the following subkeys (depending on
whether you installed MSDE as the default MSDE instance or as a named instance:
HKEY_LOCAL_MACHINE\Software\Microsoft\Microsoft SQL Server\<Instance Name>\MSSQLServer\
- In the right-pane, double-click the LoginMode subkey.
- In the DWORD Editor dialog box, set the value of this subkey to 1. Make sure that the
Hex option is selected, and then click OK.
- Restart the MSSQLSERVER and the SQLSERVERAgent services for
this change to take effect.
Security best practices for a SQL Server installation
Each of the items that follow will make your system more secure
and they are part of the standard security "best practices" for any SQL Server
- Secure your sa login account with a non-NULL password. There are worms that only
work if you have no security for your sa login account. Therefore, to make sure that the built-in sa account has a strong password, you must follow the recommendation
provided in the "System Administrator (SA) Login" topic in SQL Server Books
Online, even if you never directly use the sa account.
- Block port 1433 at your Internet gateways, and then assign
SQL Server to listen on an alternate port.
- If port 1433 must be available on your Internet gateways,
enable egress and ingress filtering to prevent misuse of the port.
- Run the SQLServer service and SQL Server Agent under a
Microsoft Windows NT account, not a Local System account.
- Enable Microsoft Windows NT Authentication, and then enable
auditing for successful and failed logins. Then, stop and restart the
MSSQLServer service. Configure your clients to use Windows NT
For more information regarding how a blank sa password can be
exploited, click the following article number to view the article in the Microsoft Knowledge Base:
PRB: Unsecured SQL Server with blank (NULL) SA password leaves vulnerability to a worm
For more information about a change in behavior with post-SQL Server
2000 Service Pack 1 when the authentication mode changes, click the following article number to view the article in the Microsoft Knowledge Base:
FIX: If you change Windows Security to Windows/SQL Security, the SA password is blank