Hosting ASP.NET Web App on IIS DB connection problems

Question

I have used IIS before, but I've never used a database and I've never done a web app. I did the same steps for putting a site onto IIS and everything works EXCEPT for when I go to a page that has a DB connection on it. I've tried a lot and this is all I get.

A network-related or instance-specific error occurred while establishing a >connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: SQL Network Interfaces, error: 50 - Local Database Runtime error occurred. Cannot create an automatic instance. See the Windows Application event log for error details.

Windows Application Event Log:

Cannot get a local application data path. Most probably a user profile is not loaded. If LocalDB is executed under IIS, make sure that profile loading is enabled for the current user.

This was built in Visual Studio and I have a SQL Express DB. I posted my connection strings, any help is greatly appreciated.

I have added this to my applicationHost.config:

<add name="DefaultAppPool">
    <processModel identityType="ApplicationPoolIdentity" loadUserProfile="true" setProfileEnvironment="true" />

And now I get:

An attempt to attach an auto-named database for file |MY DB1 FILE| failed. A database with the same name exists, or specified file cannot be opened, or it is located on UNC share.

<add name="DefaultConnection" connectionString="Data Source=(LocalDb)\MSSQLLocalDB;AttachDbFilename=|DataDirectory|\DB1.mdf;Initial Catalog=aspnet-ICCAA_VIZIER-20150223043129;Integrated Security=True" providerName="System.Data.SqlClient"/>
<add name="ConnectionString" connectionString="Data Source=(LocalDB)\MSSQLLocalDB;AttachDbFilename=|DataDirectory|\DB2.mdf;Integrated Security=True;Connect Timeout=30" providerName="System.Data.SqlClient"/>

Answer 1

I was able to figure it out. I changed all my data connections to .\\SqlExpress . Which led me to another error of:

Login failed for user 'NT AUTHORITYNETWORK SERVICE'

To fix this I followed this guys article to figure it out.

Login Failed For user NetworkService