How do i go about creating an exception handler when i want to login to my form to access the rest of my forms. The username and password are linked to server.What if it doesnt connect to server? here is coding for me to login:

 Private Sub btnLogin_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnLogin.Click
    If (txtUName.Text = "-") Or (txtUName.Text = "0") Or (txtUName.Text = "") Or (txtPass.Text = "0") Or (txtPass.Text = "-") Or (txtPass.Text = "") Then
        MessageBox.Show("Invalid Entry", "ErrorMessageBox", MessageBoxButtons.OK, MessageBoxIcon.Error)
        txtUName.Text = ""
        txtPass.Text = ""
    End If
    empeid = txtUName.Text
    sqldLoginadapter.SelectCommand.Parameters("@EID").Value = txtUName.Text
    sqldLoginadapter.SelectCommand.Parameters("@EPass").Value = txtPass.Text
    sqldLoginadapter.Fill(DatasetLogin1, "empdetails")
    If (DatasetLogin1.Tables("empdetails").Rows.Count > 0) Then
        MessageBox.Show("Login Successfull! Welcome Employee: " & empeid, "MessageBox", MessageBoxButtons.OK, MessageBoxIcon.Information)
        txtUName.Text = ""
        txtPass.Text = ""
        MessageBox.Show("Not Registered Employee Details!. Please Try Again", "ErrorMessageBox", MessageBoxButtons.OK, MessageBoxIcon.Error)
        txtUName.Text = ""
        txtPass.Text = ""
    End If
End Sub


Whenever u write a coding for Database connection use the try catch block


' *ur complete code goes here * 

Catch ex as Exception
MsgBox(ex.Message) ' if u get an error in above coding it will be passed to catch block and will display the error
End try

And also use the finally bloack to close ur connection to database or to dispose any objects...