Sounds like it is hanging when you exit and later try to restart Firefox. Generally, the cause is an Extension or a Plugin. * How to stop the running Firefox process ** In Task Manager, does firefox.exe show in the '''<u>Processes</u>''' tab? ** See: http://kb.mozillazine.org/Kill_application * What may cause Firefox to hang at exit ** http://support.mozilla.com/en-US/kb/Firefox+hangs ** http://kb.mozillazine.org/Firefox_hangs ** https://support.mozilla.com/en-US/kb/Firefox+is+already+running+but+is+not+responding * You may need to try Firefox Safe Mode ** You may need to use '''Safe Mode''' to locate the problem: http://kb.mozillazine.org/Safe_Mode **Firefox Safe Mode is a diagnostic mode that disables Extensions and some other features of Firefox. If you are using a theme, switch to the DEFAULT theme: Tools > Add-ons > Themes '''<u>before</u>''' starting Safe Mode. When entering Safe Mode, do not check any items on the entry window, just click "Continue in Safe Mode". Test to see if the problem you are experiencing is corrected. ** If the problem does not occur in Safe-mode then disable all of your Extensions and Plug-ins and then try to find which is causing it by enabling '''<u>one at a time</u>''' until the problem reappears. '''<u>You MUST close and restart Firefox after EACH change</u>''' via File > Restart Firefox (on Mac: Firefox > Quit). You can use "Disable all add-ons" on the Safe mode start window. ** See the following for more information *** http://support.mozilla.com/en-US/kb/Troubleshooting+extensions+and+themes *** http://support.mozilla.com/en-US/kb/Troubleshooting+plugins *** http://support.mozilla.com/en-US/kb/Basic+Troubleshooting -------------------------- '''Other issues needing your attention''' The information submitted with your question indicates that you have out of date plugins with known security and stability issues that should be updated.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. *Adobe Shockwave for Director Netscape plug-in, version 11.5.9.615 **'''''Security update 11.5.9.620 released 2011-02-08''''' *Adobe PDF Plug-In For Firefox and Netscape "9.4.1" **Update to version 9.4.2 (released 2011-02-08) or Reader X (version 10) **Reader X (version 10) ***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 *Next Generation Java Plug-in 1.6.0_18 for Mozilla browsers **6 updates behind **'''Security update 1.6.0_24 released 2011-02-10''''' #'''Check your plugin versions''': http://www.mozilla.com/en-US/plugincheck/ #*'''Note: plugin check page does not have information on all plugin versions''' #'''Update Shockwave for Director''' #*NOTE: this is not the same as Shockwave Flash; this installs the Shockwave Player. #*Use Firefox to download and SAVE the installer to your hard drive from the link in the article below (Desktop is a good place so you can find it). #*When the download is complete, exit Firefox (File > Exit) #*locate and double-click in the installer you just downloaded, let the install complete. #*Restart Firefox and check your plugins again. #*'''<u>Download link and more information</u>''': http://support.mozilla.com/en-US/kb/Using+the+Shockwave+plugin+with+Firefox #'''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 [[Java]] plugin''' to the latest version. #*Download site: http://www.oracle.com/technetwork/java/javase/downloads/index.html (Java Platform: Download JRE) #*Also see "Manual Update" in this article to update from the Java Control Panel in Windows Control Panel: http://support.mozilla.com/en-US/kb/Using+the+Java+plugin+with+Firefox#Updates #* Removing old versions (if needed): http://www.java.com/en/download/faq/remove_olderversions.xml #* Remove multiple Java Console extensions (if needed): http://kb.mozillazine.org #*Java Test: http://www.java.com/en/download/help/testvm.xml