The application “Eclipse” can’t be opened. (macOS Monterey)

I downloaded Eclipse on my Mac for school, following these instructions:

In your browser, go to Eclipse Downloads. Do not use the Eclipse Installer. Instead follow these steps to download and install Eclipse.

Find the Eclipse IDE for Java Developers package (make sure you do not pick the wrong package) and click on the appropriate download link for your operating system (Windows, Mac, or Linux) and architecture (32-bit or 64-bit). There are many other packages but this is the one that you’ll need in this class.

Once the download has completed, locate the downloaded file. This file will be a compressed (i.e., a “.zip”, or “.tar.gz”) file. Uncompress this file into the directory of your choice. It doesn’t really matter where you put the Eclipse installation folder as long as you know how to retrieve it. You can optionally create a shortcut of the Eclipse IDE executable file (“eclipse.exe” on Windows, or “eclipse” on Linux, or “Eclipse” on Mac OS X) found in the directory that is created. To start Eclipse you just double-click on the executable file or the shortcut

I downloaded the Eclipse macOS x86_64 version, and moved it into my applications folder. I was able to open Eclipse, and everything works perfectly, and I can work if it’s open; but after I close Eclipse and a couple hours go by, I get the following messages once I try to reopen it. “Eclipse quit unexpectedly” and “The application “Eclipse” can’t be opened.”

I had the .dmg file in my downloads folder, which might have been the problem. I moved it into my applications folder with Eclipse, and that still doesn’t work.

I have tried to delete and redownload Eclipse multiple times, and nothing works.

do you have any suggestions on how I can fix this?

Answer

Faced the same issue each time I’m restarting the Macbook pro M1, and a random Reddit thread provided me with a way to fix it. Open a terminal and run,

sudo codesign --force --deep --sign - /Applications/Eclipse.app

Not sure why this codesigning fixes the problem. But seems to be a bug in the eclipse itself. Hope this helps someone.