See: *https://support.mozilla.com/en-US/kb/Unexpected+installation+error+-203+when+installing+add-ons *http://kb.mozillazine.org/Unable_to_install_themes_or_extensions_-_Firefox#Unexpected_installation_error_-203 <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 '''Other issues needing your attention''' The information submitted with your question indicates that you have out of date plugins with known security and stability issues that should be updated.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. '''''Security pdates for all of the following were released early in February 2011.'''''<br /> <br /> *Adobe Shockwave for Director Netscape plug-in, version 11.5.9.615 *Adobe PDF Plug-In For Firefox and Netscape **Current versions are 9.4.2 and 10.0.1 (aka Reader X) **More info about version 10.0.1 (aka 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 10.1 r102 *Next Generation Java Plug-in 1.6.0_23 for Mozilla browsers #'''''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 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 [[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 #'''Update the [[Java]] plugin''' to the latest version. #*Download site: http://www.oracle.com/technetwork/java/javase/downloads/index.html (Java Platform: Download JRE) #**'''''Be sure to <u>un-check the Yahoo Toolbar</u> option during the install if you do not want it installed. #*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