MSSQL cannot connect to wentasy-pc/sqlexpress user ' sa ' Logon failure error 18456 resolution

Environment: SQL Server 2008 R2

Problem: Unable to connect to wentasy-pc/sqlexpress user ' sa ' Logon failure error 18456

As shown in figure:

Solve:

1. Open database------> Login to database with Windows------> Security------> Login------> double-click SA------> Set Password------> Click Status on the left menu bar------> Login------> select start------> OK

2. Right-click the server name------> Properties------> Click Security in the left menu------> select SQL Server and Windows Authentication mode------> OK

3. Close connection------> Login to database with SA------> Resolve

Description

Even if SQL Server and Windows identity mixed authentication mode are selected during installation, problems can still occur when you log on with the SA, which can be resolved by referring to the method in this article.