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Created 12/2/15. Updates available online.

Windows

FAQs

When I attempt to open a Java sim, Windows will try to open the sim with a program other than Java (Word, Internet Explorer, etc.) or give me the message "This XML file does not appear to have any style information associated with it."

Sometimes, the Java file associations can become broken. Follow these steps to re-associate both '.jnlp' and '.jar' files to use Java:

1. Download both a '.jar' and '.jnlp' from our website - "Download" and "Run Now", respectively.
2. For each file, right click and choose 'Open With..."
3. Select "Choose Default Program"
4. Check the "Always use the selected program to open this kind of file"
5. Click the "Browse..." button
6. For ',jnlp' select "JavaWS.exe" (located here on a default installation: C:\Program Files (x86)\Java\jre7\bin\) For '.jar' select "Java.exe"
7. Click "Open".
8. Click "OK"
9. The '.jnlp'/ '.jar' file should now open in Java.

I am using Windows 8, when I try to open the sim I get a dialog asking me to find an app to run the sim.

There are two versions of Windows 8: 'RT' and 'Pro'. All of our simulations will work on a 'Pro' operating system. The 'RT' version of Windows 8 doesn't allow Java to be installed, but you can use our new HTML5 simulations as well as our Flash simulations. If you have the 'Pro' version of Windows 8, you can go here to install Java: http://www.java.com/en/ and once that it finished you should be able to run all of the simulations.

The two versions of Windows 8 provide very different possibilities in terms of accessibility. You can find your Windows version http://windows.microsoft.com/en-us/windows/which-operating-system

If you still encounter problems on the 'Pro' version after verifying that Java installed, it may be that the file associations are not correctly pointing to Java to open '.jar' and '.jnlp' files. Please follow the instructions above to re-associate the files with Java.

Why can't I completely uninstall the PhET sims that I downloaded from my Windows computer?

When a Java Web Start simulation is run in Windows, it is added to the list of programs in Control Panel -> Add or Remove Programs. Due to a problem in Java Web Start, sometimes the item may remain in the list even after the simulation has been removed, and Windows may report "Unable to completely uninstall application". More information about this issue can be found at http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6946221, and the producers of Java have acknowledged the problem and reported that they plan to fix it in an upcoming version of Java.

Why is a simulation with 3D graphics not launching / displaying correctly?

If a simulation that uses 3D graphics is not launching or displaying correctly, updating your video card's drivers may fix the issue.

For Windows XP / Vista / 7:

  1. Press the Win + R keys.
  2. type "DxDiag" and press enter.
  3. After the diagnostic tool opens, the video card name and manufacturer will be listed in the Display tab under Device.
  4. Go to the driver manufacturer's website to find an up-to-date driver. The most common video card manufacturers are Nvidia, AMD, and Intel
  5. Follow all instructions to download and install the latest driver, then restart your computer.
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