Login failed for user 'sa'. (Microsoft SQL Server, Error: 18456)

We are able to connect to MSSQL Server Management Studio with Windows Authentication but unable to connect with SQL Server Authentication. The 'sa' login details are correct but still getting the following error message:

Login failed for user 'sa'. (Microsoft SQL Server, Error: 18456)

 

In order to resolve the issue, please refer to the following steps:

1. Login to the MSSQL Server Management Studio with Windows Authentication.
2. In SQL Server Management Studio Object Explorer, right-click the server, and then click Properties.
3. Under the Server Properties, select a page of "Security".
4. Select the Server authentication as "SQL Server and Windows Authentication mode" and click Ok.
.

 5. Restart the SQL Services and then try to login with 'sa' details.

 

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我按照这样操作，sa登陆成功了。其实这不是什么技术方面的问题，但是sql本来自身的配置不常操作，如果没有什么经验的话，遇到这种问题也是比较麻烦。

出现这中问题其实就是ssms客户端程序配置的问题，装完数据库后，默认的设置是禁用 SQL Server Authentication 即SQL Server身份认证，只启用Windows认证模式。

希望你遇到这样的问题的时候，可以看到这篇转载的文章!