I have a child page LoginContent.aspx which contains a login form. If the user logs in he should be redirected to my Welcome.aspx page. But if I press the login button the page just reloads itself, nothing happens. The codebehind on this page is empty. Both LoginContent.aspx and Welcome.aspx are child forms of the same master page.

<form method="post" action="~/Welcome.aspx">
    Username: <input type="text" name="username" size="15" /><br />
    Password: <input type="password" name="passwort" size="15" /><br />
<input type="submit" value="Login"/></p>
</form>

I know I could use the asp.net login control but I want more control over things.