if you want to update the database but you don't what data were modifiedin your grid, since you bound you grid to the dataset then use the dataset to check what are the changes being done in the grid...

use a loop that will check the mdichild's forms then close them and then open the form you wanted to open...

For Each frm As Form In Me.MdiChildren
frm.Close()
Next

Dim frm1 As...

add also in your login checking about sql injection or else it will be easily to hack...

actually I don't understand what you mean...well but if you mean to show their different error messages in one messagbos only, maybe this would help.


Dim ErrMessage As String

If Lastname.Text...