I've the following VB code to connect to MSSQL 2005 express edition:

Imports System.data.sqlclient
Imports System.Data.SqlServerCe

Public Class Form1

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim CONStr As String = "Server=192.168.1.5;database=pos;user id=sa;password=123"
Dim ccon As New SqlConnection(CONStr)
Try
ccon.Open()
MsgBox(ccon.State)
Catch ex As Exception
MsgBox(ex.Message)
End Try

End Sub
End Class

tried to write the port 1433 after I configured the sql setting to accept TCP/IP port 1433 and delete 0 from dynamic.
I wrote many connection string like:
"data source=192.168.1.5,1433\Sqlexpress;initial catalog=pos;user id= sa;password=123"
or
"data source=192.168.1.5\Sqlexpress;initial catalog=pos;user id= sa;password=123"
or
"data source=Mycom_name\Sqlexpress;initial catalog=pos;user id= sa;password=123"

the error message was (sql exception error) and another one was (a native exception has occurred in xyz.exe

what is the problem?