Failed to unpack natives: Socket read timed out {#welcome}

This error is caused when certain files fail to properly download, and are incorrectly "skipped" by the launcher, believing that the file already exists, while it in reality does not.

This in return, gives an error when the game tries to open a couple of files, and it actually realizes that the file does not exist, returning the java.util.zip.ZipException: error in opening zip file exception.

What causes this error

SocketTimeoutException can be caused by many issues, which include but are not limited to:

Faulty antivirus and or firewall {#firewall}

Believe it or not, at times, antiviruses and firewalls can do more harm than good.

We recommend that you remove any to help troubleshoot the issue.

Malware, or hijacked files {#malware}

Certain malware, is known to cause errors when creating "sockets" to external sites.

We reccommend that you use a free utility such as MalwareBytes to clean your computer of such.

Latency to servers {#latency}

It is a growing assumption that this error is caused by an abnormal latency to Minecraft's servers.

NOTE: None of these fits your issue? Still not working? Contact our support resources!

Firewalls and antiviruses

Certain firewalls and antiviruses are known to have issues with Minecraft.

It is recommended that you un-install them, if you are using one.

You can check what AntiVirus you are using by holding the Windows key, then pressing "R".

In the Run dialogue, type in "appwiz.cpl" and press OK.

Search for anything that has "Security", "Firewall", or "Antivirus" as a keyword, and you should be able to pinpoint the antivirus or firewall application that you are using, and also un-install it.

NOTE: Make sure you know what you are removing, else you could get unexpected output!

Malware, or hijacked files

Having malware installed on your computer is not only harmful to the game, but also affects your system.

There are several utilities out there which serve the purpose of removing, clearing and identifying malware, or hijacked files on your computer.

The utility that we reccommend is Malwarebytes , which can be used, free of cost.

We reccommend that you run a Full scan on your computer to identify all possible intruded files.

Latency to servers

Server latency may also be the cause for these errors.

Please do the following to help diagnose if there is an issue with communicating with Mojang's servers;

NOTE: It is advised that you contact our support resources to guide you through this process!

Windows

Press your Windows and R keys at the same time to bring up a "Run" dialogue.
Enter in "cmd" and then press OK.
Execute the following command: tracert libraries.minecraft.net.
After a while the command will finish, and give a bit of output.
If you look to the third row, you should see a bunch of numbers, if any of them are >80ms, then this can indicate that there is an issue.

Mac OSX

Open a terminal, you can get to it by searching "Terminal" at spotlight.
Execute the following command: traceroute libraries.minecraft.net.
After a while the command will finish, and give a bit of output.
If you look to the right, you should see a bunch of numbers, if any of them are >80ms, then this can indicate that there is an issue.

robot56/gist:8090113