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Red X image displayed where the applet should be. Applets won't run


This article applies to:
  • Browser(s):
    Internet Explorer 5.5, Internet Explorer 6.x, Netscape 6.2x, Netscape 7, Mozilla 1.4+
  • JRE version(s):
    1.5.0

SYMPTOM(S)
An applet does not load, and the "Java Plug-in Control Panel" shows the following error:
  • java.net.UnknownHostException: www.xxxxx.com
    at java.net.PlainSocketImpl.connect(Unknown Source)
  • Or, you see an image that looks like a small white box with a Red X in it
  • Or, the browser cannot display the program, and shows the error message
    "Loading Java Applet Failed..."

Error: Loading Java Applet failed...
CAUSE
  • The Java Runtime Environment (JRE) could not obtain proxy information from the browser.
  • The JRE is not configured correctly


SOLUTION
Start the Java Plug-in Control Panel by following these instructions:
  1. Click the Start menu
  2. Select Settings
  3. Select Control Panel
  4. Double click the Java icon.
  5. Click on the Network Settings button.

Network Settings dialog box
  1. Select the Use Browser Settings checkbox.
  2. Click the OK button to save your changes.

Network Settings for the Java Control Panel
  1. Close all browser windows. Restart the browser and try to load the applet.
  2. If the applet still does not load and you see the same connection error, try to configure your web browser's proxy settings.

Related information:
What is a proxy server? How do I get proxy server information?


Web Browser Proxy Configuration
The web browser proxy settings are set as either manual or automatic. Please choose from the instructions below to configure your proxy settings for the browser.
  1. Manual Proxy Configuration
  2. Automatic Proxy Configuration
  1. Manual Proxy Configuration
    1. Internet Explorer
    2. Mozilla

    1. Manual Proxy Configuration: Internet Explorer
      1. From the Internet Explorer menu bar, click Tools.
      2. Select Internet Options.
      3. Click the Connections tab.
      4. Click LAN Settings button.
      5. Click Advanced button. The Proxy Settings dialog box appears.

Internet Explorer Proxy Setting Example
      1. Enter the proxy information. Check with your ISP or Sysadmin to get the proxy settings.
      2. Click OK
    1. Manual Proxy Configuration: Mozilla
      1. From the Mozilla menu bar, click Edit.
      2. Select Preferences.
      3. Expand the Advanced menu by clicking the + sign.
      4. Select Proxies.


Mozilla Proxy Setting Example
      1. Copy each address and port number to the corresponding entry into the "Proxies" Tab inside the Java Control Panel utility.
        1. Click the Start menu
        2. Select Settings
        3. Select Control Panel
        4. Double click the Java icon.
        5. Click on the Network Settings button.
        6. Select Use Proxy Server checkbox
        7. Click Advanced button

Proxy Setting Example: JRE Advance Network Settings Dialog Box
  1. Automatic Proxy Configuration

    2. If your network administrator provides an automatic proxy configuration script, Java Runtime Environment can use the same script to configure itself automatically. Please follow the instructions below to get proxy information from the proxy configuration script.
    1. Internet Explorer
    2. Mozilla

    1. Automatic Proxy Configuration: Internet Explorer
      1. From the Internet Explorer menu bar, click Tools.
      2. Select Internet Options.
      3. Click the Connections tab.
      4. Click LAN Settings.

IE Automatic Detection of Proxy Setting Example
      1. Input the same script name from "Automatic Proxy Configuration URL" field into the "Java Control Panel".
        • Click Start > Settings > Control Panel.
        • Double-click the Java icon.
        • Click the General tab.
        • Click Network Settings.
        • Select Use automatic proxy configuration script checkbox.
        • Enter same script name and path as entered in your web browser.

JRE Automatic Detection of Proxy Setting Example
  1. Automatic Proxy Configuration: Mozilla
    1. From the Mozilla menu bar, click Edit .
    2. Select Preferences.
    3. Expand the Advanced menu by clicking the triangle sign.
    4. Select Proxies.

Mozilla Automatic Detection of Proxy Setting Example
      1. Input the same script name from "Automatic Proxy Configuration URL" field into the "Java Control Panel".
        • Click Start > Settings > Control Panel.
        • Double-click the Java icon.
        • Click the General tab.
        • Click Network Settings.
        • Select Use automatic proxy configuration script checkbox.
        • Enter same script name and path as entered in your web browser.

JRE Automatic Detection of Proxy Setting Example
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




Help Resources
> Installing Java
> Configuring Java
> Error Messages
> Applet Application
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