The Ask Toolbar is causing that in the Firefox 3.6.x versions. Uninstall that extension.

There are a couple of places to check for the Ask toolbar:

• Check the Windows Control panel for the Ask Toolbar - http://about.ask.com/apn/toolbar/docs/default/faq/en/ff/index.html#na4
• Also check your list of extensions, you may be able to uninstall it from there - https://support.mozilla.com/kb/Uninstalling+add-ons

-> Tap ALT key or press F10 to show the Menu Bar

-> go to Help Menu -> select Restart with Add-ons Disabled

Firefox will close then it will open up with just basic Firefox. Now do this:

-> Update Firefox to the latest version by going to Help Menu -> About Firefox -> click Check for Updates -> if an updated version is found then download the latest version and install it. After that follow these steps:

-> Update ALL your Firefox Plug-ins https://www.mozilla.com/en-US/plugincheck/

-> go to View Menu -> Toolbars -> unselect All Unwanted/Incompatible Toolbars

-> go to Tools Menu -> Clear Recent History -> Time range to clear: select "EVERYTHING" -> click Details (small arrow) button -> place Checkmarks on Cookies, Cache -> click Clear Now

-> go to Tools Menu -> Options -> General -> in Startup section click Reset to Default button

-> go to Tools Menu -> Options -> Content -> place Checkmarks on:

1) Block Pop-up windows 2) Load images automatically 3) Enable JavaScript

-> go to Tools Menu -> Options -> Security -> place Checkmarks on:

1) Warn me when sites try to install add-ons 2) Block reported attack sites 3) Block reported web forgeries 4) Remember Passwords for sites

-> go to Tools Menu -> Options -> Advanced -> Network -> Offline Storage (Cache): click Clear Now button

-> Click OK on Options window

-> click the Favicon on SearchBar -> click Manage Search Engines -> select all Unwanted Search Engines and click Remove -> click OK

-> go to Tools Menu -> Add-ons -> Extensions section -> REMOVE All Unwanted/Suspicious/Incompatible Extensions (Add-ons) -> Restart Firefox

-> go to Tools Menu -> Add-ons -> Appearance section -> REMOVE All Unwanted/Suspicious/Incompatible Themes (Persona) -> Restart Firefox

You can enable your Known & Trustworthy Add-ons and Themes later. Check and tell if its working.

Well, the problem is fixed... against my desire I broke down and uninstalled Firefox 3.6 and installed 4.0, but this didn't fix the problem. Then I uninstalled 4.0 and installed 5.0 and the 'open new tab' function is working again. After reading the 2 replies, I uninstalled and removed all traces of the Ask Toolbar. I never wanted it in the 1st place.

Thanks for such quick response help.

You're welcome.

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