How to get a Java™ VM

The standard Java VM is provided by Sun as a browser plug-in called the Java Runtime Environment (JRE).

Microsoft used to provide its own Java VM for Windows Internet Explorer. Internet Explorer does not now include a Java VM, so you must download the Sun VM. Microsoft have withdrawn their Java VM.

Some browsers originally came with a built-in Java VM.  For browsers such as Netscape 7 and Opera, you usually have the option of including a Java VM in your download.

If you have a Java VM already, then you may need to update it.  For example, some old Microsoft Java VMs have problems running phdcc applets on CDs.  See below for upgrade instructions.

If a Java VM is not bundled with your browser installation, these are your download options:

Sun Java VM

The Sun Java Plug-in is a Java VM for Microsoft Internet Explorer, Netscape 6/7 and other browsers.
Download the Java Plug-in from Sun, approx 7-16MB.  If automatic detection does not work, manually get the appropriate Java Runtime Environment (JRE).

Windows only:
	Installing the Sun Java Plug-in optionally installs the Java VM into both Internet Explorer (IE) and Netscape 6/7 (N6,N7) / FireFox.  Close all browser windows and restart your browser.
	The Java VM Plug-in can be configured in the Control Panel. This displays the Plug-in version and lets you activate/deactivate the Sun Java VM in Internet Explorer and Netscape.
	After installing the Java Plug-in and restarting your browser, go to a page containing a Java applet (eg here). You should then see the Sun Java logo in the taskbar notification area. If you double-click on the taskbar logo, then the Java Console window appears.  As shown below, this also tells you the Java Plug-in version, ie 1.4.0 in this case.  Some Java applets will add further information to the Java Console which may be useful if diagnosing runtime problems. If the Sun Java logo is not in the taskbar, you probably need to enable it in the Java Plug-in Control Panel - select "Hide console" to show the taskbar logo but hide the console itself until you want to see it.

If installed in Opera, select menu "Window+Special+Java Console" to see the Opera Java Console window.

Microsoft Java VM

Microsoft no longer distribute their Java VM, although you can update an installed Java VM as described below. They say: "Microsoft is committed to helping customers through the transition off the Microsoft® Java Virtual Machine".

If you install the Sun VM then this will usually be used in preference to the Microsoft VM.  However you can remove the Microsoft VM.  Search for the removal tool called "unmsjvm" - one possible location.  This unzips into a folder of your choice - then run the unzipped file also called unmsjvm.exe after reading Readme.rtf.  Read these instructions carefully to ensure that the Sun VM still works after running the removal tool.  You have to remove a registry entry and re(install) the Sun VM for it to work.

More information from Microsoft.

For some versions of Windows, Windows Update Catalog will let you download a VM installation/update - do an advanced search for "VM".

If you are using phdcc's Java applets, you can download our copy of the Microsoft Java VM - click here.

Apple Mac

Mac OS X includes the Sun Java VM for use with the Safari browser. Update this using the System Properties Software Update feature: the "OS X 10.2.6" and "Java 1.4.1 Update 1" updates are recommended, though large.

Netscape 7.1 for Mac OS X includes the Sun Java 1.3.1 VM - it does not use the above OS X Java 1.4.1.

For Classic Mac OS 8.1 and 9, download the Mac OS Runtime for Java (MRJ).

For further information, see Apple's main Java site and their developer Java site.

To check for updates, open the Java Plug-in Control Panel, select the Update tab and click on the "Get Java Update" button. Your browser will now open at the Sun web site and tell you if there is an update available.

Alternatively, get your current version number by opening the Java Plug-in Control Panel or the Java Console, as described above.  Compare this against the latest J2SE version listed here.

If you need to do an update, download the latest version and install it.  You do not need to uninstall the previous version first, although it might be tidiest to do so.

If you already have the Microsoft VM installed then you can update it at Windows Update. This is the preferred option as it will by definition be up to date. Alternatively, if you are using phdcc's Java applets, you can download our copy of the Microsoft Java VM - click here. This can be used to update a Java VM installation. To find your current Microsoft VM version, select menu "View+Java console" in Internet Explorer. The version is the last number on the right, ie 3805 in this example: If the Java Console menu option is not available, select menu "Tools+Internet Options" Advanced tab, then scroll down to the "Microsoft VM" (see picture below right) and check the box "Java console enabled"; then close all browser windows and restart.

If both the Microsoft and Sun Java VMs are installed, you can switch between them in menu "Tools+Internet Options" Advanced tab.  In the screenshot shown on the right, the Sun VM is in use (and so the Microsoft VM is therefore disabled).  If you change any of these settings, then you need to close all browser windows and start IE again.

Service Pack 2 (SP2) for Windows XP includes improvements to Internet Explorer security that are intended to help most users by stopping web pages that contain "active content" from accessing your computer maliciously. However these improvements make it harder to run Java applets in pages stored on your computer (as opposed to those viewed on the web). This includes applets used in documentation pages and those used on CDs or DVDs. We have serious concerns about the problems XP SP2 causes for local content. We did try to persuade Microsoft to accommodate such uses in a more friendly way. For most cases, simply "allowing blocked active content" in the new Information Bar will let the Java applet run without any problem, although you will have to brave some dire-sounding warnings. However this is not enough to let our FindinSite-CD software run fully. There are new security options in Internet Explorer that avoid these warnings (and run FindinSite-CD) - if you are prepared to check them. Open menu Tools+Internet Options+Advanced tab, then scroll down to the Security section - see screen shot on right. To run active content on CDs, make sure that "Allow active content from CDs to run on My Computer" is checked. To run active content anywhere locally then make sure that "Allow active content to run in files on My Computer" is checked.

Java and all Java-based marks are trademarks or registered trademarks of Sun Microsystems, Inc. in the U.S. and other countries.

Comments:

hars, Mon, 19 Sep 2005 14:21:00 (GMT)

i am not able to load bdk1.1 on my system(which has win xp pro). it is giving java vm is not supporting or reinstall java vm

Pawan Kumar Bhatia, Fri, 3 Mar 2006 01:41:17 -0700

Thank you for providing valuable informations about the setting of JRE configuration.

Ron Malloy, Tue, 18 Apr 2006 15:03:08 (GMT)

I'm not sure how things will work out as I proceed, but the infomation about changing my Internet Options {Advanced} was helpful!