Disable back key in browser

Add this script inside head tag in html page 

<script type = "text/javascript" >

   function preventBack(){window.history.forward();}

    setTimeout("preventBack()", 0);

    window.onunload=function(){null};

</script

Cross Browser HTML and CSS Compatibility

If you follow XHTML and CSS standards according to the XHTML and CSS version then no need to worry about the browser compatibility ..




Check your pages whether it follow using ,

http://validator.w3.org/

http://jigsaw.w3.org/css-validator/

http://www.w3.org/QA/Tools/

.Net Document Viewer

http://www.aspsnippets.com/Articles/Display-Word-document-on-web-page-in-ASP.Net.aspx