I WAS trying to install netbeans,but it is showing an error to install jdk which is already in my system.
when i checked the envirnmental ariables i found sysvariables original path was deleted so what should i do .to get my previous settings??
Try a System Restore back to before you did that.
How to Do a System Restore in Windows 7http://www.sevenforums.com/tutorials/700-system-restore.html