Sa Login Failure SQL Server Error 18456 Solution

Yesterday, my SQL (Microsoft SQL Server 2005) failed to log on. It turned out to be a few small issues. Now I want to record my solutions to these problems. (There are many solutions. These are just my solutions for your reference)

Troubleshooting process: (Note: You can still log on with a Windows account)

Step 1: Start all SQL-related services, and the problem persists;

Step 2: view the Windows Firewall. It is started by default. If the option is disabled, it is disabled.

The two prompts "due to security considerations, some settings are controlled by group policies" "Windows Firewall is using your domain Settings", first use gpedit. in the MSC grouping Policy Editor, choose "Computer Configuration"> "management template"> "network"> "network connection"> "Windows Firewall"> "standard configuration file". Check that the properties of each option on the right are not configured. The problem is not here.

As mentioned in another prompt, the domain settings cannot disable SQL Server, and I check that the local open ports (Net start), 1434, and are all in the development status.

Dizzy, will it be a wrong password?
Problem 1: I forgot the SA logon password for logging on to Microsoft SQL Server 2005.

Solution: use Windows authentication to log in, and then right-click 'sa '-'properties' in 'security'-'logins'. Change the password and click confirm.

Problem 2: A connection has been established with the server, but an error occurs during logon. (Provider: Shared Memory provider, error: 0-there is no process on the other end of the MPs queue .) (Microsoft SQL Server, error: 233)

Solution: Open 'project'-'All projects'-'Microsoft SQL Server 100'-'configuration tool'-'SQL Server Configuration Manager'. In the displayed form, find 'SQL Server 2005 network configuration', start "named pipes" and "TCP/IP" under the 'mssqlserver Protocol', and then restart Microsoft SQL Server 2005.

Problem 3: The default database cannot be opened. Logon Failed. User 'sa 'Login Failed. (Microsoft SQL Server, error: 4064)

Solution: use Windows authentication to log in, and then right-click 'sa '-'properties' in 'security'-'logins' to set the default database to a master, click OK.