I have a login page, it is redirected to an login check page. If the logon is not sucessfull the user or rather the page is redirected back to the original login page with a message. If the login is sucessfull then the page is redirected to a statistic page were the user then can view certain stats.

After uploading when typing eg http://aaa.com/stats.asp all the stats all the users is dispalyed. How can I prevent this.

Yours stats.asp page needs to check whether the person trying to view it has logged in, if they haven't it should redirect them to your login page.

To do this you can use cookies or session variables, theres lots of free scripts out there to help you do this.
Try a quick search on Google, if your still stuck pm me.

on you login page set the following sessions:

'Check if already login
If Session("username")="" Then
Session("username")="VisitorUserName"
Session.Timeout=30 'in minutes
Else
response.redirect("stats.asp")
End if



On your stats page insert these code on top:

If Session("username")="" Then
response.redirect("login.asp")
Else
Display Stats Belongs to Session("username") value
End If