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JavaScript Error javascript.JSException: Unknown name

This article applies to:
  • Platform(s): Windows 7, Vista, Windows XP, Windows 2000, Windows 2003, Windows 2008 Server, Windows ME
  • Browser(s): Internet Explorer, Firefox, Chrome
  • Java version(s): 6.0


When loading the webpage an error is displayed:
JavaScript Error javascript.JSException: Unknown name


Some possible causes are:
  1. The JavaScript is not enabled in browser.
  2. The browser does not support JavaScript technology.
  3. The web page has a JavaScript programming error.


JavaScript is a Netscape technology. For additional information about JavaScript, visit

Follow these instructions to enable JavaScript technology in the web browser:

Internet Explorer
From the browser menu bar:
  1. Select Tools > Internet Options
  2. Click the Security tab
  3. Click Custom Level
  4. Dialog box: Security Settings
  5. Scroll down to find Scripting of Java applets
  6. Click Enable
  7. Click OK
  8. Click OK
Mozilla Firefox
From the browser menu bar:
  1. Select Tools > Options
  2. Click Web Features
  3. Select the Enable JavaScript checkbox
  4. Click OK
  1. Open Google Chrome browser
  2. Enter chrome://settings/content in the address bar
  3. Select the option to Allow all sites to run JavaScript (recommended)

If JavaScript technology is already enabled in the web browser, then the error message indicates that there is a programming error in the JavaScript code.
Contact the webmaster of that site to report the error including the:
  1. Error message
  2. Type and version of the browser used
  3. URL of the web page that displayed the error message
  4. Steps to reproduce the error

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