my computer suddenly stopped allowing me to open new windows in firefox, how do I reset it to do this

Try uninstalling the Ask toolbar and it should work again. There is a compatibility issue with the Ask toolbar and Firefox that prevents new tabs from being opened.

how do I do that, since I never consciously installed the ask toolbar

The Ask toolbar can get installed when you install something else. Your user agent string shows that it has been installed. See the section on uninstalling extensions in this link - https://support.mozilla.com/kb/Uninstalling+add-ons

The suggestion by TonyE will remove the toolbar from Firefox. To remove the Ask Toolbar completely from your entire system, see: *http://about.ask.com/apn/toolbar/docs/default/faq/en/ff/index.html#na4 <br /> --------------------------- <br /> '''Other issues needing your attention''' The information submitted with your question indicates that you have out of date plugins with known security and stability issues that should be updated. To see the plugins submitted with your question, click "More system details..." to the right of your original question post. You can also see your plugins from the Firefox menu, Tools > Add-ons > Plugins.<br /> <br /> *Adobe PDF Plug-In For Firefox and Netscape **Current versions are 9.4.2 and 10.0.1 (Reader X) **More info about version 10.0.1 (Reader X) ***New Adobe Reader X (version 10) with Protected Mode was released 2010-11-19 ***See: http://www.securityweek.com/adobe-releases-acrobat-reader-x-protected-mode *Shockwave Flash 10.0 r32 **Very old version #'''''Check your plugin versions''''' on either of the following links': #*http://www.mozilla.com/en-US/plugincheck/ #*https://www-trunk.stage.mozilla.com/en-US/plugincheck/ #*'''Note: plugin check page does not have information on all plugin versions''' #'''Update Adobe Reader (PDF plugin):''' #*From within your existing Adobe Reader ('''<u>if you have it already installed</u>'''): #**Open the Adobe Reader program from your Programs list #**Click Help > Check for Updates #**Follow the prompts for updating #**If this method works for you, skip the "Download complete installer" section below and proceed to "After the installation" below #*Download complete installer ('''if you do <u>NOT</u> have Adobe Reader installed'''): #**Use the links below to avoid getting the troublesome "getplus" Adobe Download Manager and other "extras" you may not want #**Use Firefox to download and SAVE the installer to your hard drive from the appropriate link below #**Click "Save to File"; save to your Desktop (so you can find it) #**After download completes, close Firefox #**Click the installer you just downloaded and allow the install to continue #***Note: Vista and Win7 users may need to right-click the installer and choose "Run as Administrator" #**'''<u>Download link</u>''': ftp://ftp.adobe.com/pub/adobe/reader/ #***Choose your OS #***Choose the latest #.x version (example 9.x, for version 9) #***Choose the highest number version listed #****NOTE: 10.x is the new Adobe Reader X (Windows and Mac only as of this posting) #***Choose your language #***Download the file, SAVE it to your hard drive, when complete, close Firefox, click on the installer you just downloaded and let it install. #***Windows: choose the .exe file; Mac: choose the .dmg file #*Using either of the links below will force you to install the "getPlus" Adobe Download Manager. Also be sure to uncheck the McAfee Scanner if you do not want the link forcibly installed on your desktop #**''<u>Also see Download link</u>''': http://get.adobe.com/reader/otherversions/ #**Also see: https://support.mozilla.com/en-US/kb/Using+the+Adobe+Reader+plugin+with+Firefox (do not use the link on this page for downloading; you may get the troublesome "getplus" Adobe Download Manager (Adobe DLM) and other "extras") #*After the installation, start Firefox and check your version again. #'''Update the [[Managing the Flash plugin|Flash]] plugin''' to the latest version. #*Download and SAVE to your Desktop so you can find the installer later #*If you do not have the current version, click on the "Player Download Center" link on the "'''Download and information'''" or "'''Download Manual installers'''" below #*After download is complete, exit Firefox #*Click on the installer you just downloaded and install #**Windows 7 and Vista: may need to right-click the installer and choose "Run as Administrator" #*Start Firefox and check your version again or test the installation by going back to the download link below #*'''Download and information''': http://www.adobe.com/software/flash/about/ #**Use Firefox to go to the above site to update the Firefox plugin (will also install plugin for most other browsers; except IE) #**Use IE to go to the above site to update the IE ActiveX #*'''Download Manual installers'''. #**http://kb2.adobe.com/cps/191/tn_19166.html#main_ManualInstaller #**Note separate links for: #***Plugin for Firefox and most other browsers #***ActiveX for IE