Press these three keys together: Option, Command, and Esc (Escape). Or choose Force Quit from the Apple menu in the upper-left corner of your screen. (This is similar to pressing Control-Alt-Delete on a PC.) Then select the app in the Force Quit window and click Force Quit. How do I find (and kill) processes that listen to/use my tcp ports? I'm on mac os x. Sometimes, after a crash or some bug, my rails app is locking port 3000. I can't find it using ps -ef.

What are startup items?

Startup items, or login items, are services and applications that launch every time you start your Mac. These are applications that sneak into startup items without notice, never asking if you need or want them there. This way you may end up with a dozen apps launching as soon as you turn on your Mac, weighing heavily on its processor and memory capacities and slowing it down. Such items can increase your Mac’s startup time and decrease its performance.

Plus, sometimes when you remove an application or a service, it leaves a login item with a broken link. These broken login items are completely useless, cause unwanted messages, and waste your Mac's resources (because they look for non-existent applications). Whether you're running macOS Catalina or El Capitan, or earlier — it's all the same, so just read on.

So, let's go over how to take control of login items, and how to get rid of unwanted, broken or hidden startup items.

How to disable startup programs?

How To Kill Frozen App On Mac

Do you want to stop programs from running at startup? There’s an easy way to remove programs from startup and get your Mac to load faster on launch. The fastest way to turn off startup items on Mac is an app like CleanMyMac X.

1. Download CleanMyMac for free.
2. Launch the app.
3. Open Optimization tab.
4. Click on Login items.
5. From the list of apps, disable the ones you don’t need on startup.
6. Done!

How to change startup programs manually?

Disabling Mac startup programs is possible manually. Therefore, if you have some time and would like to do it yourself, follow the steps below.

How To Kill Apps On Macbook

Your login items are listed in settings. One of the easiest ways to control startup items is inside System Preferences > Users & Groups.

1. Open System Preferences.
2. Go to Users & Groups.
3. Choose your nickname on the left.
4. Choose Login items tab.
5. Check startup programs you want to remove.
6. Press the “–” sign below.
7. You’re done.
8. If you need to add an item back, press “+” and choose the app you’d like add.
9. Then restart your Mac to see the changes.

How to fix broken startup items?

Broken Mac startup files are left there because some part of apps are left on your Mac long after you’ve moved the app to the Trash. To get rid of these parts and to fix your startup, you’re going to need CleanMyMac again. First, you need to check if they’re among startup items and disable them if so. You can do it following the instructions above. Then you need to remove app leftovers. CleanMyMac works fine on macOS High Sierra and earlier OS.

1. Launch CleanMyMac.
2. Choose Uninstaller tab.
3. Scroll through the list of apps.
4. If you spot any app that you’ve deleted, check them.
5. Delete the app leftovers you’ve chosen.

You can also find and remove broken login items with the help of System Junk module:

1. Choose System Junk tab.
2. Click Scan.
3. Review details and click Clean.

Finally, you need to clean your macOS startup items through launch services:

1. Open Maintenance tab.
2. Choose Rebuild Launch Services.
3. Hit Run.
4. Done.

Once you do it, all broken app data on your Mac will be fixed.

How To Kill Apps On Macbook Pro

Remove daemons and agents from startup process

If speaking of files, first go to the system folder /Library/StartUpItems. Here you’ll find all the startup files that are being launched with the system. You can delete the login item you think is necessary if you’re totally sure what you are doing.

Also, the /Library/LaunchDaemons folder contains a bunch of preference files that define how the application that is being launched along with the system should work. You might want to delete some of these files as well if you know you don’t need them and removing them is safe.

The /Library/LaunchAgents contains preference files responsible for the apps that launch during the login process (not the startup).

The above-mentioned folders contain app-related files. However, you can also check system folders to review whether you need some of the system applications to be running on startup:

1. /System/Library/LaunchDaemons - note that besides preference files this folder contains other important system items that are recommended to keep untouched.
2. /System/Library/LaunchAgents - most probably, you won’t also find anything worth removing in this folder, however, keeping this location in mind might help you find files related to a problematic app that causes troubles on Mac startup. If you have a problematic application that messes about on login, you can try to trace it back from this folder.

But, if you’re looking for simple ways to remove login items, we suggest using a professional Mac utility. Download CleanMyMac X for free and make unwanted and broken login items a thing of the past.

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Macintosh is a lovely and high-performance machine. But still there are times when an application will suddenly stop responding in your Mac computer. Mouse will also appear to be hung. You would want to close the hung application. Following method will help you force close such applications.

First of all, of course, you should try to close a not responding app in the normal way. Go to app’s menu and select Quit. Alternatively, you can press Command+Q to close the app. If these methods don’t work, then you would need to use a bit of force!

Force Quit Mac Apps

Method 1

1. Press Command+Option+Escape keys on your Mac computer (it’s just like using Ctrl+Alt+Del on a PC)
2. A window will come up showing names of the running apps. Select the app that you want to close.
3. Click Force Quit button

Method 2

If mouse is working, you can use Apple menu to terminate a hung application.

1. To open Apple menu click on the black Apple icon given in the top-left corner of the screen.
2. Mac OS will show (Not responding) next to the frozen applications. Select an app that is not responding, and then click Force Quit option to get rid of the hung application.
3. If you will select an application that is not showing (Not responding) — then you can use the Relaunch button to close the app and launch it again.

There are other methods also to forcibly close a not responding app on Mac. But the above two methods are easiest and would suffice in most of the situations.

How To Kill Apps On Mac

If you have any questions on this topic, please let us know. We will try our best to assist you. Thank you for using TechWelkin!