In my code i use this instruccion 'RegisterClientScriptBlock' for register javascript code and excute it in a postback, but when i go back in explorer's history the registered javascript code before is executed again.

How can i remove this code, and prevent it from executing again?

Thanks

When you go back in your browser, you are going to be 're-loading' all of the data and markup that was rendered in that previous visit to the page. So if it contained a script (due to using RegisterClientScrptBlock), then its going to use it again. No real way to change it, as it's just how the browser works.

Best way around it is to create your own back button on your pages. Just make it a link (or a button) that when clicked, will navigate to the page which was previous to the current one.

Thanks, I was imagining it