Building from the response of @remenechelli, you can find this solution by googling "downloading apache netbeans 12.1" and choosing the netbeans link with the corresponding title. For some reason I cannot include a link in the post. Here is a more in depth explanation for anyone who isn't familiar with the command line Essentially, as remenechelli described, use this command cd /Library/Java/JavaVirtualMachines to go to the appropriate folder to see the JDK version folder's you have. I have one version folder, "jdk-11.0.7.jdk". Use the "cd" command to go into the version folder of the version you'd like to use (for me: cd jdk-11.0.7.jdk), then use cd Contents/Home to get to your JDK version home directory. This is the directory your app launcher needs to use in order to start NetBeans. Normally it can find this on it's own, but we can explicitly tell it where to look as well, which is what we need to do to run NetBeans 12.1 on BigSur. From here you can use the "pwd" command to print the path to the home directory you are in, which will look very similar to this: /Library/Java/JavaVirtualMachines/jdk-11.0.7.jdk/Contents/Home Copy this path, then use this command to get to the netbeans folder with the configuration file you need to edit. cd /Applications/NetBeans/Apache\ NetBeans\ 12.1.app/Contents/Resources/NetBeans/netbeans/etc use a text editor to open the netbeans.conf file in this folder: vim netbeans.conf If you are using vim (or vi), scroll to the bottom(ish) of the file where you'll see #netbeans_jdkhome="path_to_file" Press the "I" key to enter Insert mode. Remove the pound symbol at the beginning and replace pathtofile with the path you copied (with double quotes around it). mine looks like this: netbeans_jdkhome="/Library/Java/JavaVirtualMachines/jdk-11.0.7.jdk/Contents/Home" To exit insert mode press the "esc" key. Then to save and quit the vim/vi text editor, type ":wq". You should now be able to launch NetBeans 12.1 on BigSur.