How to Fix Internal Exception: in Minecraft

Few things are as frustrating as running into error codes, especially when you have no idea what the problem might be.

What kind of error is: Internal Exception:

Simply put it is a connection error, where the computer you are on is trying to establish a connection to the Minecraft server you have chosen and that connection gets interupted while traveling between the server and your computer.

What is the solution to this error?

Let’s start solving this problem with some basic solutions that work for almost any error. Don’t skip these unless you have already tried them, because these are the simplest solutions that take the least amount of time!

  • Restart Minecraft.
  • Restart your Computer.
  • Powercycle your Router, by turning the power to it off for a minute and starting it up again.

If these didn’t help it is time to try some of the more advanced steps.

Enabling the Native Sandbox

  • Go to the search bar on the Windows Task Bar, usually at the bottom of your screen, and type in “Control Panel” and click on the entry that pops up.
  • Find a section with a header “Programs” and click on that header.
  • On the following screen you should see an icon for “Java”. Click on the header. We have marked the Java header and icon in red in the below graphic.
Screenshot showing the Java Program and it’s Control Panel pop up
  • You should now have a small pop up labeled “Java Control Panel”. In it switch to the “Advanced” tab and start scrolling down until you see a section labeled “Advanced Securrity Settings”. We have marked this section in red in the graphic above.
  • Here you will find an option for “Enable the operating system’s restricted environment (native sandbox)”. Make sure it is checkmarked, then click “Apply” and then click “OK”.
  • It is very important that you now restart your computer, so that the changes can take effect.
  • After restarting your computer, start up Minecraft again and see if the connection to the server now holds.


Hopefully this solution helped you fix the Internal Exception: error and let you get back to playing Minecraft. If not then you might want to take to the Minecraft Forum to find some more information.