Fix: Minecraft Internal Exception: java.io.IOException

Running into the Minecraft Internal Exception: java.io.IOException error can leave you confused. But fret not! Here are some easy ways to fix it.

Encountering perplexing error codes while playing Minecraft can be quite vexing, especially if they hinder you from connecting to a server and savoring the game with your friends.

One of the best examples of such cases is the Internal Exception: java.io.IOException error that many users in the Minecraft community have encountered.

Luckily, as confusing as this error might look, it’s easily solvable using the methods we listed in the guide below.

So, without further ado, let’s take a look at what you need to know.

Table of ContentsShow

The Problem Explained

When it comes to the Minecraft java.io.IOException error, most of the time, the cause of this problem is your internet connection.

The error occurs when you are unable to connect to the Minecraft server after the game attempts to do that multiple times in a row. Some users reported seeing this error after being disconnected from the server they were already playing on.

In both cases, the outcome is losing connection to the server and being unable to reconnect.

As a result, users are shown an error screen with the “Internal Exception: java.io.IOException: An Existing connection was forcibly closed by the remote host,” as shown in the image below.

Minecraft Internal Exception java.io.IOException

Several users also confirmed that this is nine out of ten times a connection-related issue, as discussed in this specific Reddit thread where the user experiencing the same error posted their console logs indicating that the problem Is indeed related to the connection.

Although this problem can look rather confusing, and the error message does not lead to the problem’s cause, it’s still relatively easy to fix, and we’re about to show you how.

Take a look at the sections down below to learn more about which methods to apply when dealing with the Minecraft java.io.IOEXception error.

Fix 1: Power Cycle Your Router

Router

Restarting your router can resolve different issues with your internet connection, some of which may be accountable for the error you’re currently encountering when attempting to play Minecraft.

It’s an easy solution that only requires the press of a button and takes no longer than a few minutes to get done, which is why we recommend trying it out first.

To power cycle your router, all you need to do is switch it off using the physical power button, which most of the time is located at the back of the device, and then wait five minutes before powering it up again.

While waiting for those five minutes to go by, we suggest restarting your computer as well, since a couple of users verified that it assisted them in instantly resolving the issue. Afterwards, once both your connection and PC are operational, launch Minecraft and check if the problem persists.

This method helped multiple users, but it may not work for everyone. If it didn’t work for you, don’t worry, as there are still other things you can try.

Fix 2: Change Your DNS Settings

Settings

Many users reported that changing their DNS settings helped them solve the error that’s causing random disconnects while playing on free online Minecraft servers.

In one of our guides, we cover the benefits of changing your DNS over to using the settings from Google. We recommend doing the same thing now that you are experiencing the Minecraft Internal Exception error.

Before you get into it, you can also read more about the benefits of using Google’s Public DNS in their official article covering this topic and the reasons to make this change.

With that out of the way, let’s take a look at how you can change your DNS settings on Windows 10 so that you can avoid the Minecraft java.io.IOException error.

  1. Click Windows + S on your keyboard to open the search box. Then, type in Settings and press Enter on your keyboard.
  2. Now that you’re in the settings panel click on the Network & Internet section to open it.
    Windows Settings Network & Internet
  3. Click on the first setting under the “Advanced Network Settings” category called Change Adapter Options.
    Windows Change Adapter Options
  4. You will now see a list of network connections available on your computer. Right-click the one you’re currently connected to and choose Properties from the list of options.
    Windows Network Connection Properties
  5. Choose Internet Protocol Version 4 from the list of options, then click Properties, located in the bottom-right corner of the window.
    Properties for Internet Protocol Version 4
  6. Select “Use the following DNS server addresses” at the bottom of the window in the panel that’s currently open on your screen, and then type the numbers in the fields as shown in the image below.
    Windows Use the following DNS server addresses

Note: If you cannot load the image, here are the values that you need to input in text form:

  • Under “Preferred DNS server,” you need to input: 8*8*8*8
  • Under “Alternate DNS server,” you need to input: 8*8*4*4

Finish the process and confirm the changes by clicking the OK button at the bottom of the window.

Now you can launch Minecraft and attempt joining the server you previously couldn’t. The problem should no longer persist.

Fix 3: Allow Minecraft Through Your Firewall

Firewall

Being unable to connect to a specific server or getting disconnected from one while playing can be a problem caused by your firewall.

Your firewall is supposed to protect you from malicious files and potentially harmful connections, but sometimes it ends up blocking safe connections, such as the one Minecraft tries to establish to the server you’re trying to connect to.

To ensure this isn’t the cause of the problem, we recommend adding Minecraft as an exception within your firewall’s settings. This helped some users, and it could work for you as well.

Here’s how to do it:

  1. Press Windows + S on your keyboard at the same time to open the Windows search panel, then type in Firewall & Network Protection and press Enter on your keyboard.
  2. Inside the panel, scroll down and click on the Allow an app through the firewall option, as shown in the image below.
    Windows Allow an app through the firewall
  3. Add the Minecraft executable file as an exception, and then confirm the changes within the panel.

Now, your firewall will ignore Minecraft, knowing that it’s safe for your system’s health, and it won’t attempt to block any connection that the game tries to establish to the server.

This should help you get rid of the problem immediately, as it helped other users as well.

Fix 4: Try A Different Internet Connection

Internet Connection

Since this is a connection-related problem the majority of the time, we recommend benchmarking yours to see if the ping or the overall bandwidth is within the normal values.

Having an extremely high ping can automatically make the server kick you when trying to join it, or if you have so-called “lag spikes,” it can disconnect you while you are already on it.

Both of these factors can lead to the java.io.IOException error you’re grappling with.

The optimal way to check your connection’s performance is by using speedtest by Ookla, as it takes just a click and a few seconds of waiting to see the results.

In case you see a high ping or poor connection performance, it is advised to try using another one if possible.

Conclusion

With that said, you now know how to deal with the Minecraft Internal Exception error that’s quite popular amongst the community.

By applying one or all of the methods listed in the guide above, you should be able to restore your ability to play Minecraft on your favorite online servers once more. We hope this was helpful to you. 

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Bojan Veselinovikj
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Bojan is a video-game developer and a tech enthusiast. Combining these two passions allow him to keep you informed on everything that's new in this fast-paced digital world.