User ' IIS apppool\xxxx ' logon failed

First, the phenomenon
After publishing to IIS, the following prompt appears on the web site
异常详细信息: System.Data.SqlClient.SqlException: 用户 ‘IIS APPPOOL\IdealTest‘登录失败。

Second, the reasons for analysis
1. View the database connection string in the Project Web. config file:Integrated Security=True;


2. Open IIS, view the application pool, use the Integrated authentication mode, which is identified as applicationpoolidentity, causing a connection database error

Third, the solution

1. Modify the SQL Server connection string and log in with the database account password

Server=localhost;uid=sa;pwd=xxxx;database=master;

2.IIS Manager--Application pool--the corresponding program pool of the Web site--"identity-" changes the applicationpoolidentity under the process model to LocalSystem

User ' IIS apppool\xxxx ' logon failed