Sounds like a bad malware infection, or at least a bad add-on. Here's my suggested procedure for tracking down and cleaning out browser hijackers. Sorry for the length -- it's not as bad as it looks:

(1) Open the Windows Control Panel, Uninstall a Program. After the list loads, click the "Installed on" column heading to group the infections, I mean, additions, by date. This can help in smoking out undisclosed bundle items that snuck in with some software you agreed to install, as well as innocent-sounding programs with misleading names. Take out as much trash as possible here.

(2) Open Firefox's Add-ons page using either:

• Ctrl+Shift+a
• "3-bar" menu button (or Tools menu) > Add-ons

In the left column, click Plugins. Set nonessential and unrecognized plugins to "Never Activate".

In the left column, click Extensions. Then, if in doubt, disable (or Remove, if possible) unrecognized and unwanted extensions.

Often a link will appear above at least one disabled extension to restart Firefox. You can complete your work on the tab and click one of the links as the last step.

Any improvement?

(3) You can search for remaining issues with the scanning/cleaning tools listed in our support article: Troubleshoot Firefox issues caused by malware. These on-demand scanners are free and take considerable time to run. If they finish quickly and especially if they require payment, you may have a serious infection. I suggest the specialized forums listed in the article in that case.

Success?

In researching this further, V9 also may tamper with program shortcuts, i.e., the icons you use to start your browsers. In the case of Firefox, right-click the shortcut, click Properties, then on the Shortcut tab, for 64-bit Windows 7 the "Target" should be no more and no less than the following:

"C:\Program Files (x86)\Mozilla Firefox\firefox.exe"

If there is anything tacked on at the end, make sure to remove it.