基础提供程序在打开时失败

Question

I know this question has been asked a few times already, but I tried all the solutions I found on stackoverflow and everywhere else and nothing worked, so I'm asking again I'm sorry

I used to connect to a remote database on a server, but to test some things I had to backup this database and restore it locally. The thing is, when I try to replace the server name by ".\\SQLEXPRESS" in the connection strings, everytime I try to use the database (juste display datas as exemple), I got the error you can see in the title.

I already tried to Allow remote connections in my local DTC, I tried to open the connection, tried the sp_users command, nothing worked

Here is my connection string :

    <add name="HDPreDiagEntities" connectionString="metadata=res://*/HDPreDiag.csdl|res://*/HDPreDiag.ssdl|res://*/HDPreDiag.msl;provider=System.Data.SqlClient;provider connection string=&quot;data source=.\SQLEXPRESS;initial catalog=HDPreDiag;persist security info=True;user id=id;password=password;MultipleActiveResultSets=True;App=EntityFramework&quot;" providerName="System.Data.EntityClient" />

Thanks guys for your time and help

Answer 1

Okay so I tried to create a .UDL file, and when I tried to connect with SQL id, it didn't work. I just tried to connect with Windows NT security, opened the .UDL with notepad and copied the connection string in my App.config and it works fine now.

If anyone know why I couldn't connect with my DB ids, I'd be glad to hear (knowing that they exist...)