VB.NET app deployment

I have an VB.NET app that connects to a local SQL SERVER EXPRESS database

On the computer I developed the application everything works ok but when I try to deploy the application on another computer with SQL SERVER EXPRESS installed an error message appears : << under the default settings SQL SERVER does not allow remote connections. (provider :SQL Network Interfaces, error 26 : Error Locating Server/Instance Specified) >>

Is it the connection string that is bad or the fact the on my machine I have an SQL SERVER EXPRESS instance named COMPUTER\MYNAME and on the deployment machine I have another instance name

If using SQL Express then ComputerName\SQLExpress (this is a named instance).

that's exactly my problem ... ComputerName is different for every computer I install the application ... it must be an environment variable that emulates the ComputerName in VB.NET

For example if my computer has ComputerName='MAKKO' and the computer I must install the application has the ComputerName='SOMETHINGELSE' on my computer the environment variable has to be MAKKO and on other computer the environment variable should be SOMETHINGELSE

You shouldn't be using the machine name at all. This is from www.connectionstrings.com:

Quote:

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Data Source=.\SQLExpress;Integrated Security=true;AttachDbFilename=|DataDirectory|\mydb.mdf;User Instance=true;

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That is also what VS does by default when you add a SQL Server database to your project.

You can also use "(local)" instead of the dot.

thank you jmcilhinney ...

So i should use Data Source=.\SQLExpress; if I install an SQLExpress named instance

If i decide to install the default instance I would use Data Source=.; or
Data Source=(local); ???

And another question regarding SQL SERVER instalation ... At the 4th step of instalation USE THE BUILT IN SYSTEM ACCOUNT ... Should I choose Local System ? or Local Service / Network

If I enter myself the following code :

AppDomain.CurrentDomain.SetData("DataDirectory", "C:\Program Files\Microsoft SQL Server\MSSQL.1\MSSQL\Data")
Dim sqlconn As String = "Server=.;AttachDbFilename=|DataDirectory|test.mdf;Database=test;Trusted_Connection=Yes;"

string strSQL = “select * from table1”;
SqlDataAdapter dataAdapter = new SqlDataAdapter(strSQL, strCon);
SqlCommandBuilder commandBuilder = new SqlCommandBuilder(dataAdapter);
DataTable table = new DataTable();
table.Locale = System.Globalization.CultureInfo.InvariantCulture;
dataAdapter.Fill(table);
dbBindSource.DataSource = table;
dbGridView.AutoResizeColumns(DataGridViewAutoSizeColumnsMode.AllCellsExceptHeader);
dbGridView.ReadOnly = true;
dbGridView.DataSource = dbBindSource;

I get the result I want ...

But sometime I need to bind the tables to datagridview not from code but from designer ... And the designer creates automaticly an connection string like "Data Source=MYCOMPUTERNAME;Initial Catalog=test;Integrated Security=True"

What can I do so the designer creates an connection string like "Server=.;AttachDbFilename=|DataDirectory|test.mdf;Database=test;Trusted_Connection=Yes;"


Thx

SQLExpress is always a named instance. You don't have a choice in that.

I resolved the problem ...

At the SqlServerExpress instalation :

- selected the 'default' instance
- selected the 'local system'

In the code if I want to connect without designer I create myself the connection string like "Server=.;AttachDbFilename=|DataDirectory|test.mdf;Database=test;Trusted_Connection=Yes;"

If I want to connect with designer the connection strings will look like "Data Source=MYCOMPUTERNAME;Initial Catalog=test;Integrated Security=True"
and I will replace mannualy the MYCOMPUTERNAME string with '.' character

For me that worked very well