Browsers both IE and Firefox can start behaving unlikely. Whenever one try to open certain websites especially the computer security or if try to navigate directly to internal pages of certain websites, the browser window would close leaving  no information on what made them close.

That behavior of browsers is due to either a corrupt installation of Java or an outdated version of Java being the sole responsible piece of software on any system causing  browsers to crash. It means whenever download or upgrade any software or application, it should be done through original and reliable source.

There is a small fix of it. Just update your java client through sun microsystems or reinstall the latest version. One can find the download at

http://www.java.com/en/download/index.jsp 

Tags: browser-security, Java security, java-client