Regardless of the operating system you are using, clicking THIS LINK should automatically download (less than 1.5 MB!), install and start the Molecular Workbench software. If not, please proceed to the following instructions.
MW runs on Windows, Mac OS X v10.4+, and Linux. The only requirement is that the Java Runtime Environment (JRE) of Java 2 Platform, Standard Edition (J2SE) v1.5 or higher version must be installed. If you are a Windows or Linux user, and have not installed the required Java software, please download or update it from java.com. The entire Java installation process is Web-based and automatic, similar to installing Macromedia Flash. Mac OS X users can update to the latest Java through the Software Update under the "System Preferences" menu.
If you are in a network that prevents you from installing anything (as networks in most schools do), please contact your network administrator.
Something you should know about MW:MW is a simulation program that needs considerable horse power of your computer. It is strongly recommended that you run MW when there are no other visible programs or hidden processes (e.g. a virus scan, a backup job, and so on) running at the same time. If possible, we suggest that you also quit the currently opened programs that use a lot of computer memory. Doing so would help speed up MW and the Java Virtual Machine that supports it. You may find that MW launches slowly initially. That is because the Java Virtual Machine needs to boot before MW can run, which is a process that could take a while depending on your system. But once the Java Virtual Machine is up, MW should run faster.
MW may not run well on Windows computers older than five years, and earlier Mac OS X versions. Also, MW works the best for broadband users. If you only have dial-up access, you will probably do better if you pre-install all models and activities beforehand (use the "Option>Prefetch to Cache" menu from MW after you launch it) and choose the "Work Offline" mode from the File Menu after you have prefetched the materials you are interested in exploring.
The recommended screen resolution for Windows is 1024x768 pixels.
WindowsClick this link: "MW2.jnlp". After a few seconds, you should see the following window (the following images were taken from a Windows XP operating system --- the actual look will be different depending on your Windows version and settings):

When the downloading process completes, you will see the following information:

The above warning message is set to protect your computer security, NOT to push you off. It is a confirmation that the software you are downloading was sealed by us and has not been modified maliciously by someone. Please choose "Always". The message window will not pop up again next time you launch MW.

Please select "Yes". This will put MW to your system. You will see a desktop icon for MW:

Clicking this icon will launch MW --- you do not need the MW2.jnlp file any more. If there is an update of MW, it will download the update as well.
Right-click on this hyperlink: "MW2.jnlp", select "Save Target As..." from the popup menu, and then save the file to your desktop. Just double-click the downloaded file when you want to launch the software next time. The software has been installed onto your computer --- you do not need a browser to open it any longer. (Note: There is a possibility for Windows users using Java 1.5.0 versions that Java Web Start would fail. Click this link to see how to troubleshoot this problem.)
Mac OS X (10.4 or higher)Click this link: "MW2.jnlp". After a few seconds, you should see the following window (the following images were taken from a Mac OS X 1.4.3 operating system --- the actual look will be different depending on your OS X version):

When the downloading process completes, you will see the following information:

The above warning message is set to protect your computer security, NOT to push you off. It is a confirmation that the software you are downloading was sealed by us and has not been modified maliciously by someone. Please click "Yes" to proceed.
NOTE: This message may pop up every time you launch MW. Please click here to see how to turn it off.
If you see the following dialog window:

Please select "Yes". The next window you will see is:
NOTE: If you are using a Java 1.5.0 version older than Update 5, simply select "No". There is a bug that halts the installation process if you choose "Yes".

Please select "Save". This will put MW to your desktop. You will see a desktop icon for MW:

Clicking this icon will launch MW --- you do not need the MW2.jnlp file any more. If there is an update of MW, it will download the update as well.
Hold down the CTRL key and click on this hyperlink: "MW2.jnlp", select "Download Linked File" from the popup menu, and then save the file to your desktop. Just double-click the downloaded file when you want to launch the software next time. The software has been installed onto your computer --- you do not need a browser to open it any longer.
Some of our users have reported that MW cannot be installed or launched through Java Web Start (caused by many factors, including Java bugs, their network settings, to name a few).
The alternative is to download the Java executable mw.jar and run it directly: double-clicking on mw.jar will launch MW. When it launches, it will check if there is an update (if you are online), and if there is, prompt a dialog window asking whether or not you would like to update. For the majority of users who do not have time pressure and bandwidth limitation, we strongly recommend that you update every time.
Windows users
Mac OS X usersYou must have OS 10.4 or higher version and Java 1.5 or higher version. If you do not have the required Java version, please update through the Software Update pane of System Preferences, and then right-click or CTRL+click this link: mw.jar and save the file to your disk. After downloading it, simply double-click once and only once on it.
Linux usersYou need to install the latest Java Runtime Environment first, then download the file given by the following link: mw.jar. Double-click on mw.jar to launch MW. If it does not launch, open a x-terminal, change to the directory where it is located, and type in the following command: java -jar mw.jar. If the java command is not recognized, please also include the path (e.g. /usr/local/jdk1.6/bin, if Java is installed in the /usr/local/jdk1.6 directory).
For more information about troubleshooting, please read the FAQ.
When you run it, make sure to set a system property called mw.nosecurity to
be true in the launching command. Otherwise, the application will just hang.
To protect your users from malicious code that could be plugged into an MW page, however,
this property should not be set when you deploy your build.