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Configuring Your Web Browser

The version number displayed above may take some de-coding. For example, Internet Explorer 5 and 6 both say they are version 4 (thanks for nothing Microsoft). The correct version for IE5 and IE6 is what shows up after "MSIE". Both these browsers report the operating system after their version. Again, things are more confusing than necessary: Windows 2000 is reported by IE as Windows NT 5.0 and Windows XP is reported by IE as Windows NT 5.1. Firefox v1.0.7 says it is Netscape version 5.0. Beats me why. 

Enable Java™ software through your Web browser from Sun. Applies to Internet Explorer 5.5 and 6.x, Netscape 4.7.x, 6.2.2, 7, Mozilla 1.2.1, 1.3, 1.4, 1.4.1 and JRE versions 1.4.2_xx (where xx is from 01-99). The instructions on this Sun page for Firefox 0.8 are not correct for Firefox 1.0. 

Switching between the Microsoft VM and the Sun Java Runtime Environment (JRE) from Sun. No date. Applies to version 1.4.2_xx.

With Internet Explorer 5 and the Microsoft JVM, configuration options for Java are in two places. You access both via Tools => Internet Options.

 (1) The security tab can be used to enable or disable the JVM totally. Pick a zone (the Internet Zone being self explanatory) and click on the Custom Level button. This opens a security settings window. Scroll down to the Microsoft VM section. There is a checkbox to disable Java (under Java Permissions) and also options to set various levels of Java safety (security).
 (2) The Advanced tab has a section for the Microsoft VM that turns the Java console, Java logging and the JIT compiler on and off.

Internet Explorer 6 and the Microsoft JVM, works similarly. In the Security Settings window, there is a section called "Microsoft VM" which contains 5 possible options for "Java Permissions". One of these options is "disable Java"

From Microsoft: 
How to Troubleshoot Java Problems in Internet Explorer  Microsoft Knowledge Base Article - 168806 
How to Enable the Javalog.txt File Microsoft Knowledge Base Article - 17346

For Internet Explorer 6 with a Sun JVM:  

The Windows control panel has a Java Plugin that can configure the Java environment, including assigning Java to different browsers on your computer. 

From IE, Tools => Internet Options => Advanced Tab. When using Sun's Java there will be a section called "Java (Sun)". If a Microsoft JVM is also available, there is a section called "Microsoft VM". To enable Sun's Java, turn on the checkbox labeled "use java 2 v1.4.2_03 for <applet>". 

Even when the Sun JVM is being used, in the Microsoft VM section, the option for the JIT compiler remains on. Also, on the Security tab (Tools => Internet options) when you click on the custom level button, there is still a Microsoft VM section and Java permissions are still set to high safety when Microsoft's Java is not being used. There is no need to enable the "disable java" option, in fact, don't disable it - this disables the Sun JVM!! 

My experience using IE6 with a Sun JVM on the Version page of this web site was that IE issued a warning that the security settings prohibit the use of ActiveX controls. I can only assume this is a bug in IE, as there are no ActiveX controls anywhere on this web site. IE must be confusing the Java applet on the Version page with an ActiveX control.  

The above was from a machine running Windows XP and Java version 1.4.2_03. 

For Internet Explorer on a Macintosh, go to Edit -> Preferences -> Java (under Web Browser). Be aware of bugs affecting Java on OS X (from Mickey Segal who also has Macintosh Java Resources). 

The latest versions of Windows XP and 2000 allow you to chose a default JVM. You may have to use Windows Update to upgrade your copy of Windows so that it includes this feature. From the Control Panel, select Add/Remove Programs, then in the left hand column select "Set Program Access and Defaults". You may have to scroll down to see it, but there is a section called "Chose a default virtual machine for Java". On a Windows 2000 SP3 machine with the latest patches applied as of early January 2003, the only option was the Microsoft virtual machine. 

I have yet to try this on a computer with a Sun JVM installed. Also, it is not clear whether this effects all web browsers on your computer or just IE (my guess is that it is only for IE). Finally, I don't know if this capability exits in other flavors of Windows.

In Mozilla it is fairly simple to enable and disable Java. From the Edit menu item choose Preferences. Then click on the Advanced category to see the Advanced Preferences window. There is a checkbox for enabling Java. Note that this checkbox appears when you click on "Advanced" not on any of the sub-topics under Advanced. This was tested in both version 1.6 and version 1.3.1. 

In Netscape Navigator v4.7x and 4.8, start at the Edit menu item, select Preferences and then go to the Advanced section. There is a single checkbox that enables or disables Java.