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JavaScript Error "javascript.JSException: Unknown name"


This article applies to:
  • JRE version(s):
    1.4.2_xx



SYMPTOMS

The web page does not function as expected and displays a JavaScript programming language error:
JavaScript Error "javascript.JSException: Unknown name"


NOTE: JavaScript is a Netscape technology. For additional information about JavaScript, refer to the mozilla.org page titled, "What is JavaScript?"


CAUSE

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



SOLUTION

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

Internet Explorer

From the browser menu bar:
  1. Select Tools > Internet Options.
    Dialog box: 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

From the browser menu bar:
  1. Select Edit > Preferences.
    Dialog box: Preferences
  2. Click Advanced icon.
  3. Select Scripts & Plugins.
  4. Select the Navigator check box under Enable JavaScript for.
  5. Click OK.


Netscape

From the browser menu bar:
  1. Select Edit > Preferences.
    Dialog box: Preferences
  2. Click the Advanced icon.
  3. Select Scripts & Plugins.
  4. Select Navigator check box under Enable JavaScript for.
  5. 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.


Opera

From the browser menu bar:
  1. Select File > Quick preferences.
  2. Select the Enable JavaScript checkbox.
  3. Click OK.




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

Related topic: What is JavaScript and how is it different from Java Technology?


NEED MORE HELP?
If you require further assistance, please make sure you check through our Help and FAQ sections thoroughly. We probably have a page that answers your question.

You may find information on the following topics in the Help section:
Installing Java
Configuring Java
Error Messages
Applet Application




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> Configuring Java
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