Jarfix v.3.0.0 Free Download【2022】for Windows 10 (32-Bit/64-Bit)

Jarfix is a free utility for Java developers and anyone who often run .jar files but discover that other applications are stealing the extension. Jarfix is a safe, lightweight, simple-to-use and completely free solution for when your PC refuses to run Java files when your open files with the .jar extension.


Jarfix is a straightforward and helpful application that is both free and simple to download and install. The program aids in the recovery of .jar associations with the Java Runtime Environment. It requires a Windows-based operating system (95/98/ME/NT/2000/2003/2008/XP/Vista/7/8/10) to function, however it is not available for Mac. If you don’t have Java Runtime Environment installed, Jarfix will inform you where you can get it.

Jarfix v3.0.0 Free Download for Windows


If you doubleclick on a jar file, and your Java application does not start, your .jar association has been hijacked. You can fix the problem with Jarfix.

The problem …

The root cause for the problem above is, that a program has stolen the .jar association. If you have installed the Java Runtime Environment the first time, the file type called “jar” is assigned to javaw.exe correctly. “jar” is an abbreviation for “java archive” and javaw.exe is the correct program to execute a .jar. However, on Windows any program can steal a file type at any time even if it is already associated with a program. Many zip/unzip programs prefer to do this, because a jar is stored in the .zip format. If you doubleclick on a .jar, your pack program opens the file, rather than javaw runs the program, because your pack program ignores the meta information which are also stored in a .jar. In the Oracle bug database there is the low-priority report 4912211 “add mechanism to restore hijacked .jar and .jnlp file extensions”, but it has been closed as “Closed, Will Not Fix”.

You may also miss the file connection with .jar if you are using a free Open JDK without an installer.

The workaround …

Reinstall the Java Runtime Environment or fix the Windows Registry manually each time this problem occurs.

The solution …

You can fix this problem very easy with the small but reliable download jarfix.exe program. Just doubleclick on it to restore the .jar association with javaw.exe.


Optional parameters …

By default jarfix fixes the problem without any additional parameters. Nonetheless, there are a few optional parameters available if you want to customize the behavior of jarfix.

/64 On Windows x64 you can have both a 32-Bit JRE and/or a 64-Bit JRE installed. By default jarfix searches for the 32-Bit JRE first and if a 32-Bit JRE is not found it continues to search for the 64-Bit JRE. With the /64 option you tell jarfix to search only for the 64-Bit JRE/JDK.
/a Option /a adds the menu item called “Run as…” (Windows XP) respectively “Run as administrator” (Windows Vista and Windows 7) to the context menu of the Windows Explorer in order to execute .jar files also with administrator permissions. That can be useful for Java based installers that are stored in the .jar-format, because usually those installers want to write to the Windows program directory where normal users haven’t write permissions by default.
/h Prints some help (version, author, syntax) and quits the program.
/i sets an alternative icon for .jar files (only necessary for older JREs).
/k forces a search in the Windows Registry for a JDK only. That option skips the search for a JRE.
/I Creates a symbolic link called “latest”, that points to the JRE/JDK that jarfix can find. An alternatively name of the link can be specifies by using an .ini file. See also the section called “Optional configuration file”.
/s Runs jarfix silently (without any dialogs). That can be useful if jarfix should be launches by a different program or if you want to run jarfix by the Windows’ autostart feature.
/u Restores the .jar-association for the current user account only. You can use that option if you don’t have admin permissions on the computer. The option can be also useful if you are admin and if you  actually wan to use a different JRE than all other users on the computer.
/x Extracts four files and quits the program. the files which are being extracted are: a) jarfix-license.txt, the license of jarfix; b) jarfix.ini, a sample configuration file for the /c option; c) jartest.jar, a tiny Java programcalled Jartest which you can use in order to test the .jar-association; d) jartest-license .txt, the license of Jartest.
/z Forces a search in the Windows Registry for a JDK only from Azul Systems that has been installed latest using the .msi. That option skips the search for a JRE/JDK from Oracle.

Many parameters can be used together, for example “jarfix /64 /a /k /s /l” starts the program without any dialogs (/s), searches for a 64bit JDK only (/64 /K), recreates the file association with jar, creates a junction called latest (/I), and adds the menu item called “Run as administrator…” for jar files to the context menu of the Windows Explorer (/a).

Optional configuration file …

In order to feed jarfix with an alternate configuration file, simple create a file that has the same name as the .exe, but with .ini extension. The .ini file has to be in the same folder where the .exe is stored. With that config file you can fully control the action that should happen if you double click on a jar file. Options specified on the command line are concatenated with the options specified in the config file. Both detailed instructions and examples can be found in that sample configuration file.

Key of Features:

  • Jarfix is freeware. no need to register and pay for it.
  • Jarfix fix the .jar association with the Java runtime environment.
  • Jarfix is used in different Operating System (OS).
  • Jarfix fixes problems without any need of parameter.
  • Simple and lightweight program with 1MB.
  • Jarfix is useful for JAVA developers.
  • Lightweight software.
  • It’s easy to use.
  • It’s completely free.

Latest Update v3.0.0

  • From Java 11, Oracle does not provide a dedicated JRE anymore, only a JDK, therefore for x64 and JDK 9+, Jarfix 3 will search for a JDK first and then for a JRE, otherwise the latest.
    Java Runtime Environment could not be found if both JDK 11+ and a JRE version <11 are being installed.
  • For Oracle JDK <9 or on 32-Bit platforms, the mature search strategy remains unchained.
  • Added option /k in order to search in the Windows Registry only for a JDK and not a JRE.
  • Added support to find a JDK from Azul Systems in the Windows Registry.
  • Add option /z in order to search in the Windows Registry for a JDK from Azul Systems only.
  • Added option /I in order to create a link called “latest” that points to the latest JRE/JDK. The symlink will be stored under the JRE/JDK’s parent folder.
  • Removed option /c, because a more comfortable solution exist: if a <jarfix>.ini file exists, it will be read by the <jarfix>.exe; simply replace <jarfix> with a name of your choice.
    That way you can call jarfix with different configurations without the need to go to the command line.
    That feature is also useful for setting up a .jar file association for an OpenJDK bundle that doesn’t come with an installer (e.g. the OpenJDK from jdk.java.net or AdoptOpenJDK.net).
  • Changed all links from http to https.

Technical Setup Details

  • Software Full Name: jarfix.exe
  • Setup File Name: jarfix.exe
  • Full Setup Size: 0.7 MB
  • Setup Type: Offline Installer / Full Standalone Setup
  • Compatibility Architecture: 32-Bit (x86) / 64-Bit (x64)
  • Latest Version Release Added on Jun-10-2014
  • License: Freeware
  • Developers: https://johann.loefflmann.net/

Minimum System Requirements

  • Operating System: Windows XP/7/8/8.1/10
  • Memory (RAM): 2 GB
  • Hard Disk Space: 500 GB
  • Processor: Intel Pentium or above

Frequently Asked Questions?

What is Jarfix?

Jarfix is a free app designed primarily to help Java developers resolve the commonly experienced problem of Java-based programs not functioning correctly. Too often, this is because another program hijacked the association between the .jar files and the javaw.exe file.

How do I use Jarfix?

  • Download & Install the Java JDK. Most likely, you have already tried this step if you have a landed on this article, but it is worth mentioning just in case.
  • Download The Jarfix. After you have the JDK installed.
  • Run the Jarfix.

Can I trust Jarfix?

Yes, I’ve used it multiple times on multiple device (Desktop/Laptop) and it’s 100% safe (downloaded directly from the source here). If you keep trying to boot Optifine and it just seems to open for a sec and then close, it’ll fix it. I recommend it all the time.

Conclusion on Jarfix for Windows

I suppose you have followed each step carefully for Download Jarfix on PC. After downloading this software, open this software.

I suppose your PC does not installed this software. Then, you can download this extension from ItTechGyan website. Now import that software file to your PC.

At last, I hope you liked this post on Jarfix on Notebook!

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