I have a peculiar problem. I created an ASP.Net page with the code behind in C#. After submitting I am storing the primary key value of the row inserted in a ViewState variable. Then I pass this as a query string and do a Response.Redirect() to another page. Then I use the browser back button to come back to the previous page. I click submit again. In the submit routine I am unable the get the same value I stored earlier in the Viewstate variable for the page. My aim is this. To prevent submitting again when clicking the submit button. For this I need to store the primary key to check whether it exists in the database after navigating by the back button. Can you help?