Minecraft issues on MacBook Pro

1) Are you using the native Minecraft.app for macOS installed from the disk image (DMG) file that shows the version number in the bottom-left corner that was downloaded from mojang.com / minecraft.net? This is the latest client version for Mac:

2) I assume you are not using an old Minecraft.jar launcher from years ago or copied from another machine, or another 3rd-party launcher or 3rd-party client or possibly a Modpack launcher (Twitch, FTB, Skaia, etc.).

3) Can you login using your email address + password on mojang.com / minecraft.net web site?

4) If you do not have anything in your Minecraft installation that you care about, such as saved servers, you can delete the Minecraft Application Support folder (or move it to your desktop to be safe). It will be re-created fresh when you launch Minecraft again. Here is the Minecraft folder location. This will usually fix 90% of all issues.

~/Library/Application Support/minecraft

5) If that still doesn't work you can install the Java 8 JDK version for Mac OS 64-bit:

https://www.oracle.com/technetwork/java/javase/downloads/jdk8-downloads-2133151.html

6) If that doesn't work I strongly suspect you have a 3rd-party firewall issue or possibly a macOS firewall/privacy issue. The macOS firewall shouldn't cause any problems, but you can turn it off completely to test or better yet is to approve any blocked application like Minecraft or Java that you see. This article below shows you how:

Safely open apps on your Mac - Apple Support

(also check out the Privacy tab to see if you need to approve the app)

7) Have you tried a different network Wi-Fi network? Are you using a school or corporate network that may have some traffic blocked or just regular public coffee shop Wi-Fi or home/residential Wi-Fi?

Thanks for posting that picture. This does confirm my description of the problem so I appreciate that!

Ok, so the fact that neither your account nor other accounts work on this MacBook Pro, and that your account works fine on other computers, and the fact the problem exists on your MacBook even when using other networks, and that nobody else is experiencing this points to a network issue specifically on your MacBook that is blocking the needed network communication w/ Mojang.

These are the ports that Minecraft requires to be open:

• TCP: 25565
• UDP: 19132-19133,25565

None of these ports get block by default on the macOS firewall. And you did say (as I understand it) you tried turning off the macOS firewall. So just to be sure though you can see that under System Preferences, Security & Privacy icon, Firewall tab. I'm assuming it says Firewall: Off on that screen.

The next thing to check is to make sure your Mac isn't trying to use IPv6. Go to System Preferences, Network icon. Click the Advanced button and click on the TCP/IP tab. Is it showing that you are using IPv6 or is that part blank (like my screenshot below):

If it has any information for the IPv6 section coming up automatically, change Configure IPv6 from Automatic to Link-local only.

And just to be clear you did move the Minecraft.app into your Finder > Applications folder and are in fact running it from Applications yes? And you are not running it from a read-only Disk Image DMG file mounted into Finder? That's the last thing that can possibly be causing an issue in my book if deleting the Application Support folder doesn't help.

FYI, by deleting the Application Support Minecraft folder that gets rid of everything except the Minecraft.app. All you need to rebuild your install is to simply launch the Minecraft app. You, yourself, won't have to redownload anything but the app itself will download all the needed files during your first launch. So it will simply take a couple minutes extra to launch that first time.

BTW, in terms of what is happening is that your client is not able to authenticate your account with Mojang's login server. Without that you can only play in Single-player mode, or on multi-player servers that have account authentication turned off (i.e. are running in "offline mode" aka erroneously called "cracked" servers, but they are not cracked or nefarious at all). To run in any normal multiplayer server running in "online mode" (includes Mojang's own "Realms" server) you have to be able to successfully authenticate. This mechanism is what allows servers to actually ban accounts and keeps people from impersonating other people's account names. This is why I wanted to make sure it wasn't any sort of particular firewall or network issue blocking that authentication traffic occurring on just one specific Wi-Fi network.

I'm very hopeful that removing the Application Support Minecraft folder is all you need. That also forces you to set up a new launcher profile for the first time which is where I suspect the error is. And if finally doing this still doesn't fix the problem the next (ideal) thing would be if you could try a friend's account (who trusts you enough with their username+password) to show whether or not the issue is with your own account and not anyone else's.

If that's not possible, or using a friend's account has the same issue where you cannot log onto any multiple server or onto Realms, if you want to upload your log files to a drop-box or something, I'd be happy to take a look:

• ~/Library/Application Support/minecraft/logs/latest.log
• ~/Library/Application Support/minecraft/nativelog.txt
• ~/Library/Application Support/minecraft/launcher_log.txt

When you open the Minecraft app click on Launch Options and toggle the switch right below that for Advances Settings to be on.

With that setting on click on Latest Release 14.2 in the latest below.

Toggle the JVM arguments switch to be on.

You'll want to add this argument to the list of arguments: -Djava.net.preferIPv4Stack=true

To make it easier, just erase the whole line and copy and paste this into it:

-Xmx2G -Djava.net.preferIPv4Stack=true -XX:+UnlockExperimentalVMOptions -XX:+UseG1GC -XX:G1NewSizePercent=20 -XX:G1ReservePercent=20 -XX:MaxGCPauseMillis=50 -XX:G1HeapRegionSize=32M

(the only change from the default is I added that about IPv4Stack parameter as the 2nd argument after -Xmx2G)

Click Save then go back to the Settings menu tab option. Make sure you are set to "Latest Release" to the right of the PLAY button, and click the PLAY button.

Let me know if this resolves the issue my friend!

Also, if it's not an IPv6 issue you can use the following mac terminal commands to test the ports. Bring up the Terminal app in spotlight search and see if the following two commands each say "succeeded" (twice for the second one):

Or you can take a screenshot or copy/paste the output if it says anything else.

If this does not work then I have to conclude you have a 3rd-party security, firewall, VPN client (like for a corporation or university) or Proxy server set up and I can tell you how to look for that.

Awesome!