Every stinkin’ time you have to update Java (which is every day it seems, since Java has more (security) holes than most Swiss cheese) it wants to install the stupid Ask Toolbar and take over your default search engine. Here’s a quick Windows registry fix that will apparently disable the installer from even asking you about the toolbar installation.

Another way, without having to download and rename or create a new .REG file, is to copy and paste the following two lines into an elevated CMD prompt:

reg add HKLM\software\javasoft /v "SPONSORS" /t REG_SZ /d "DISABLE" /f

reg add HKLM\SOFTWARE\Wow6432Node\JavaSoft /v "SPONSORS" /t REG_SZ /d "DISABLE" /f

via Superuser: How can I prevent Ask.com Toolbar from being installed every time Java is updated?