The user ' IIS apppool\private ' logon failed.

The user ' IIS apppool\private ' logon failed.

Description: An unhandled exception occurred during the execution of the current WEB request. Check the stack trace information For more information about the error and the source of the error in your code.

Exception Details: System.Data.SqlClient.SqlException: User ' IIS apppool\private ' logon failed.

Workaround:

Application Pool Identity Changes:

At this point, try opening the link database via the Web site, prompting:

user ' NT authority\network SERVICE ' login failed.

Continue to solve,

To see if the user account exists in SQL NetworkService, method:

1) Open the SQL Manager, select, "Security"-"login name" to see if there is a networkservice, and if not, add it

2) Add Account method: Right-click "Login Name", select "New Login", in the Pop-up dialog box to the right of the login input box, click on the right of the "search", in the pop-up "Select User or group" click on "Advanced", then click "Find Now", find NetworkService user name, click OK. Then click on the left side of the "Server role", the Publick selection box, click "User Mapping", the data sheet used in your project before the tick, click "OK".

So far, you can run it again.

Final Summary:

Why did the above error occur, the check found that the Web. config connection database configuration exists trusted_connection=true;

If the trusted_connection=true is removed directly; or change to false, you can avoid the above problem.

Ps:

Trusted_Connection Trusted Connection (Trusted Connection)

When false, a user ID and password are specified in the connection. When True, the current Windows account credentials are used for authentication.
Recognized values are true, false, yes, no, and SSPI equivalent to TRUE (highly recommended)

Reference:

Http://www.cnblogs.com/sunxi/p/4277818.html

The user ' IIS apppool\private ' logon failed.