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VB.NET Sql Server Cannot Login

I had database application which works fine if it runs locally.

But running the program on other computer or via network, it fails.

It shows the error "Unhandled exception has occured in your application"; "Cannot open database db_name requested by the login."

On my application the issue was the connection string on the code.

This code below runs fine on my application. I'm using VB 2010 for my program.

con.ConnectionString = "Data Source=,1433;Database=MyDBx;User ID=dbsa;Password=db007"

1433 is the default port for Microsoft SQL; if this was changed you need to enter the correct port.

To check if port 1433 is listening for connections, open a command prompt and type:

netstat -an | find "1433"

If everything is set correctly output will show like this:

TCP               LISTENING
TCP    [::]:1433              [::]:0                 LISTENING

The string connection below was the one messing up the application that caused the program to fail and unable to login to the database remotely or using other computers on the network.

con.ConnectionString = "Data Source=DB7\SQLSRv;Database=DBx7;Integrated Security=True"

There are other possibilities that can cause this error to happen, like:

If the firewall is not configured properly to allow the traffic for the SQL, the “Authentication method” settings on the SQL server, if the username and password does not match on the login database; this scenarios can cause the application to fail.

Hope it helps.. Cheers..


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