Javax.mail Error: a Jni Error Has Occurred

Some Minecraft users are seeing an mistake whenever they effort to launch the client (the game) or the server (.jar). The fault message that comes up is: "A JNI mistake has occurred, delight check your installation and attempt again". This problem is generally reported to occur with version Minecraft version 21w19a and newer and it's confirmed to appear on Windows 7, Windows 8.1, Windows x, and Windows 11.

Equally it turns out, there are multiple causes that might trigger this error when certain users attempt to launch Minecraft and almost each of them is related to the Java installation.

Hither's a list of possible culprits that are most likely responsible for causing the "A JNI mistake has occurred, please check your installation and effort again":

Coffee sixteen JDK is missing – If you get this error while attempting to launch Minecraft build 21w19 or newer, the first thing you should exercise is check if the Java 16 JDK installation is missing from your PC. This is the about popular reason why this error is encountered when launching Minecraft on PC. If the Java 16 JDK is missing from your figurer installation, download and install it from the official channels.
Broken Organisation Path for Java – Equally it turns out, another reason why you can expect to come across this error is a scenario in which the arrangement variable path for java is cleaved and tricks the Minecraft launcher into believing that Coffee is not installed on your PC when it really is. If this scenario is applicable, you should be able to fix the issue by removing the broken system PATH variable from the Environment variables.

Install the latest Coffee JDK version

In near documented cases, this item mistake happens when y'all attempt to launch Minecraft or a Minecraft server on a PC that doesn't have Java 16 or newer installed. Keep in listen that starting with Minecraft build 21w19, y'all will need to have Coffee's 16 JDK version installed on your PC, otherwise, the game will not launch.

To ready this event, you will simply need to update your electric current Coffee JDK to the about recent version bachelor using the official channels.

If you lot're looking for step by footstep instructions on how to practise this, follow the guide below:

Ensure that the Minecraft launcher (Tlauncher or any other) is completely closed before moving to the next step below.
Open your default browser and visit the download page of the Java 15 Development kit.
Once y'all're inside, make sure the Windows tab is selected, then curl all the way down to the Windows x64 Compressed annal and click on the associate Download hyperlink.

Downloading the x65 compressed archive of the Java xvi JDK
At the confirmation prompt, check the box associated with I reviewed and take the Oracle Technology Network License Agreement for Oracle Coffee SE, and then click on the Download button beneath.
Wait until the download is complete, then unpack the cipher archive with WinZip, WinRar, 7Zip or the built-in equivalent and wait for the operation to complete.

Unzip the Java JDK
Once the extraction process is complete, navigate to the location where you extracted the JDK and copy it on your clipboard past right-clicking on it and choosing Re-create from the context card.
Next, utilize File Explorer (My Computer) to navigate to the following location and paste the JDK 16 folder that yous previously copied:
```
C:\Program Files\Java
```
Look until the copying operation is complete, then close the window and double-click on your Minecraft launcher once more (TLauncher or other).
Once yous're inside the launcher, click on the settings icon, and so click on Settings from the context carte du jour.

Accessing the Settings menu of the Minecraft launcher
Inside the Settings menu, ensure that the Minecraft Settings is selected at the top, then click the Browse push associated with Java path.
Adjacent, employ the browse window to navigate to the following location:
```
C:\Plan Files\Java\jdk-16.0.2\bin
```
One time inside, make certain that javaw.exe is selected before clicking the Open button.
Finally, click on the Salvage button to successfully salve the java path in your Minecraft launcher.
Launch the game commonly and you should come across the issue fixed.

If the trouble is however not resolved, move down to the next potential gear up below.

Remove the cleaved System Path variable for Java

If the first method was not effective in your case, the next affair you should investigate is a potentially cleaved system variable used by Java.

A cleaved variable can be the determining factor in 'tricking' your Minecraft launcher into assertive that the Java JDK requirement for the game is non installed when it actually is.

In this case, you can get the effect resolved past accessing the Arrangement Properties screen and modifying the Environment variables in a style that the Java PATH environment is removed.

This prepare has been confirmed to be effective for a lot of Minecraft users that we're encountering the "A JNI fault has occurred, please check your installation and try again" when attempting to launch the game from a defended launcher.

Follow the instructions below for a footstep-by-pace guide that volition guide yous through the process of removing the corrupted Java JDK path variable:

Note: The instructions below should work on every contempo Windows version including Windows 7, Windows 8.1, Windows ten, and Windows 11.

Printing Windows cardinal + R to open up up a Run dialog box. Next, type 'sysdm.cpl' inside the text box and press Enter to open the System Properties window.

Open up the Organization Properties window

Notation: If you are prompted past the User Business relationship Control prompt, click Yes to grant admin admission.
Once you're finally within the System Properties window, click on the Advanced tab, then click on Surround variables(under Startup and Recovery).

Open up up System Variables carte
Once you're inside the System Variables window, become to System Variables, so choose Path and click on Edit.

Editing the path variable
Next, one time yous're inside the Edit environs variable window, go alee and look for an environment variable that mentions coffee.
Once you spot the culprit, click on it in one case to select it, so click Delete to get rid of information technology.

Deleting the java environment variable
Once the problematic environment variable has been deleted, reboot your PC, then start Minecraft over again and see if the "A JNI fault has occurred, please check your installation and try once more" upshot is at present stock-still.