Exception window appears when trying to open a file

Hello,

I am new to FIJI and have just downloaded it. I am trying to open a file, but I always recieve the following exception window:

java.lang.NoClassDefFoundError: ij/plugin/PlugIn
	at java.lang.ClassLoader.defineClass1(Native Method)
	at java.lang.ClassLoader.defineClass(ClassLoader.java:763)
	at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
	at java.net.URLClassLoader.defineClass(URLClassLoader.java:468)
	at java.net.URLClassLoader.access$100(URLClassLoader.java:74)
	at java.net.URLClassLoader$1.run(URLClassLoader.java:369)
	at java.net.URLClassLoader$1.run(URLClassLoader.java:363)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.net.URLClassLoader.findClass(URLClassLoader.java:362)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:411)
	at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:349)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:411)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
	at ij.io.Opener.<clinit>(Opener.java:49)
	at ij.plugin.Commands.run(Commands.java:27)
	at ij.IJ.runPlugIn(IJ.java:199)
	at ij.Executer.runCommand(Executer.java:137)
	at ij.Executer.run(Executer.java:66)
	at java.lang.Thread.run(Thread.java:748)
Caused by: java.lang.ClassNotFoundException: ij.plugin.PlugIn
	at java.net.URLClassLoader.findClass(URLClassLoader.java:382)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:357)

Can someone help me fix this issue? Thanks.

It would probably help to include the file, or at least the file type, operating system, and any other information you have available.

Have you tried opening other file types?

I am using Mac OS and the file type is nrrd. As soon as I hit File > open the error message comes up so I can not open any file.

It sounds like something is very broken with your installation. Where did you download it from?