I'll take a few guesses.
1: You have no code.
2: You want to know how to check info put in a textbox against some list.
3: You want a form to be started after step 2 passes and a database is accessed. Otherwise a messagbox will show.
Start writing. Make your form have a text box, and figure out how to check the data when the log in button pressing event happens.
Have an if else statement checking to see if the password is okay, if not, make the messagebox tell them no. If yes, start a new form and have that form get the table from the database.
If you don't know how to do these things, start looking.
I'll even give you a start point.
http://www.functionx.com/vcsharp/controls/textbox.htm[
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