Asp.net Problem while pressing back button of browser

I have two page one is login and second is attendance..

In attendance page there is 开发者_开发百科two button In and Out visible any one of them at a time.. while i am pressing back button it navigates to previous button instead of previous page. plz give me solution for this..

That is the previous page, when you click the buttons it is doing a postback which is basically posting the form. When you hit back after posting a form, it goes to the previous page you were on, which is the form before posting. To fix this, you can use JavaScript behind the buttons instead of using the asp.net postbacks. It's hard to say exactly what you would need to do from that point without more information.