Problems with Java and Fiji - can't find ImageJ.cfg file

I want to update Java, and the instructions at say:

“This is what you need to do to upgrade to a newer version of Java:
Download and install the latest JDK from
Go to the ImageJ folder and delete or rename the jre folder
Delete the ImageJ.cfg file
Restart ImageJ and the launcher (ImageJ.exe) will generate a new ImageJ.cfg that uses the Java you just installed.”

However, I searched the entire computer and cannot find any ImageJ.cfg file.

Any ideas what to do?


You find the ImageJ.cfg file on Windows in the installation folder of ImageJ or FIJI where the executable is located, too.

For Fiji, the best place to find documentation is the ImageJ wiki

In this case, there is a FAQ entry for running with different Java versions.

Let us know if you run into any problems.

Note that this is true for ImageJ2 in general, not just Fiji—and also for many ImageJ 1.x plugins. The intent of the ImageJ wiki is to be a central resource for all things ImageJ.

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