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I can't connect to a local SQL Server instance via Entity Framework using Windows authentication

I can't connect to my local SQL Server Express instance via Entity Framework. When I try to run the update-database command, I get this error message.
Login failed for user ''. Reason: An attempt to login using SQL authentication failed.
Server is configured for Integrated authentication only.
Error: 18456, Severity: 14, State: 58.
From what I understand, Visual Studio is attempting to log in to SQL Server via a user account even though I've requested that Windows authentication is used in the connection string.
I can still access the server via SSMS.
What I've tried. None of which helped
Different variations of the connection string
Opened port 1433
Created a test UDL file to test the connection.
A clean reinstall of SQL Server Express (not sure I managed to clean up all the files)
Checked the SQL Server browser is running
Checked server instance is running
Enabled TCP/IP & named pipes
Tried connecting via tcp which works
Added Integrated Security=SSPI to connection string
Changed server to accept Windows authentication and SQL Server authentication.
Restarting PC
This is a new laptop on windows 11, I don't know if that is causing any issues as I've never had an issue with this process on Windows 10.
I seem to have two instances; .\SQLEXPRESS & (localdb)\\MSSQLLocalDB I'm not sure if this is causing some conflict or if this is the intended behaviour.
Here is the connection string, I pulled this from the server explorer within Visual Studio so I am pretty sure this is correct. On top of that, I have tried numerous variations of this to attempt to fix the issue
"DefaultConnection": "Data Source=LAPTOP-51LB4QTQ\\SQLEXPRESS;Initial Catalog=MicroBlog;Integrated Security=True;Connect Timeout=30;Encrypt=False;TrustServerCertificate=False;ApplicationIntent=ReadWrite;MultiSubnetFailover=False"
This is where I get the connection string in my Program.cs file
builder.Services.AddDbContext<BlogContext>(opt => opt.UseSqlServer(builder.Configuration.GetConnectionString("DefaultConnection")));
var app = builder.Build();
At this point I'm completely lost, I've read a lot of articles but have not come across any fixes. I'm not a dba just a programmer so have limited knowledge of this side of SQL Server.

You may try like below:
In Web.config file:
<connectionStrings>
<add name="DefaultConnection" connectionString="Data Source=SUBRATATALUKDER;Initial Catalog=MyDB;Integrated Security=True;" providerName="System.Data.SqlClient"/>
</connectionStrings>
In appsettings.json file:
"ConnectionStrings": {
"DefaultConnection": "Server=SUBRATATALUKDER;Database=MyDB;Trusted_Connection=True;TrustServerCertificate=True;",
}
Note:
Server Name = SUBRATATALUKDER
Database Name = MyDB
100% tested.

ServerVersion = 'conn.ServerVersion' threw an exception of type 'System.InvalidOperationException'

I've seen this error answered for other people, but I can't seem to get it to work. I'm trying to connect to a SQL Server Database project locally.
I'm getting this error thrown on Open() when I do the follow:
SqlConnection conn = null;
conn = new SqlConnection(connection)
conn.Open()
Where connection is a connection string passed from my webconfig. I've found examples online and tried these three connection strings and I get the same error every time:
<add name="TICKETING_CONNECTION" connectionString="Server=(local); DataBase=Ticketing_DB; Integrated Security=SSPI"/>
<add name="CONN"
connectionString="Data Source=localhost; Integrated Security=SSPI;Initial Catalog=Ticketing_DB"
providerName="System.Data.SqlClient" />
<add name="CONN2"
connectionString="Data Source=(local);Initial Catalog=Ticketing_DB;"
providerName="System.Data.SqlClient"
/>
Could the problem be stemming from the path of where the database is located on my machine? I've tried copying the c:\ path but didn't have any luck. I've seen some examples online use a .mdf file, but my project does not have this file either.
This is my first time trying to connect to a database project, so any help or advice would be greatly appreciated

If you are using Visual Studio try going to the Server Explorer and Right click on Data Connections and Add new connection by selecting DataSource as Microsoft SQL Server and provider as .net framework provider for SQL Server.
Under the server name check for the SQL Server if it is listed with your machine name.
Then try to provide the database details and user name and password for SQL Authentication or select windows for windows authentication. Then do a test connection. If it is fine on click of OK it will add the data connection.
Right click the properties of data connection which is newly added and navigate to properties to extract the connection string. Compare it with yours. This can help you troubleshoot the issue.

LocalDB not found when deploying to a different machine

I'm having a problem switching a project I am working on over to another system. It's an ASP.Net web application and web form wrapped in a single solution, with a SQL .mdf DB file in the project as well. I'd like to be able to zip up the whole thing and move it around, but when trying to debug the solution on the other machine I get an error about the local DB not existing. My connection string in the Web.Config file looks like this:
<connectionStrings>
<add name="DefaultConnection" connectionString="Data Source=(LocalDb)\v11.0;AttachDbFilename=|DataDirectory|\aspnet-name-of-database.mdf;Initial Catalog=aspnet-name-of-database;Integrated Security=True"
providerName="System.Data.SqlClient" />
</connectionStrings>
I know I must be making an obvious mistake, but I can't figure out what it is. Any advice, please? Thanks.
Edit: The specific error is:
"The specified LocalDB instance does not exist."

Run the following from your package manager console:
SqlLocalDb info
If the executable isn’t found, chances are you do not have LocalDb installed in your new machine. You can use the steps mentioned in the below link to debug as to why the connection is not successful to your localDB:
http://odetocode.com/blogs/scott/archive/2012/08/15/a-troubleshooting-guide-for-entity-framework-connections-amp-migrations.aspx

Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|\Database.mdf;Integrated Security=True;User Instance=True

Try setting the Datasource as below.
Data Source=.\;
If you are able to connect to your database, then the set the ServerName as DataSource in your connection string.
Make sure you have SSMS installed in your new system.
Download SQL Server Express 2014

Hosting ASP.NET Web App on IIS DB connection problems

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"/>

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

Entity Framework Connection to localDb

I am trying to follow the pluralsight course ASP.NET MVC 4 Fundamentals. But can't have my database connected.
Here is the error I got:
An error occurred while getting provider information from the database. This can be caused by Entity Framework using an incorrect connection string. Check the inner exceptions for details and ensure that the connection string is correct.
I have visual studio 2013 professional and SQL server 2012 installed on my machine. When I installed my SQL server, I created a server name "ABC" on my computer.
I have also installed sql localdb 11.0 separately, but it seems VS can't find the localDb connection. When I check Server Explorer -> add Connection, under server name list, only "ABC" is shown up.
Here is the connection string.
I also tried to use "Data Source = ABC; ...." it doesn't work either.
Update
Here is my connection string
<add name="DefaultConnection" connectionString="Data Source=(LocalDb)\v11.0;Initial Catalog=aspnet-eManager.Web-20141223223418;Integrated Security=SSPI;AttachDBFilename=|DataDirectory|\aspnet-eManager.Web-2014122322341‌​8.mdf" providerName="System.Data.SqlClient" />

You could try this
In server explorer, right click, Choose Add Connection
enter (localdb)\v11.0 in as the server name
Choose your database and press connect
Right click properties on your new connection
Use that connection in string in your default connection
I.e.
<add name="DefaultConnection" connectionString="<Paste-connection-string-here>" providerName="System.Data.SqlClient" />
If that doesn't work, lets try starting it from the command line
Open command prompt
Run SqlLocalDB.exe start v11.0
Follow original steps , use the named pipe as your server name
If that doesn't work, lets try and connect via named pipes
Open command prompt
Run SqlLocalDB.exe info v11.0
Copy the Instance pipe name that starts with np:...
Follow original steps , use the named pipe as your server name
e.g

Run this command to make sure what is the version of your LocalDB
sqllocaldb info
So in my case the version is MSSQLLocalDB then the connection string will look like this
<add name="DefaultConnection" connectionString="Data Source=(LocalDB)\MSSQLLocalDB;Initial Catalog=IdentityManagerDB;Integrated Security=True"
providerName="System.Data.SqlClient" />

To add on to TheGeneral use view - SQL Server Object Viewer and look immediately under the "SQL Server" object. You'll see the name of the connect looking something like "(localDB)\ProjectsV13" Hand enter that into the connection box then you can browse the server for the database you want to use.