How to open JNLP file on Windows 10 and MacOS

This tutorial explains what the JNLP file is and how to open it on macOS, Windows 10, other versions of Windows, and using Chrome and Firefox:

Every file on your system is associated with an application it runs on. Java Network Launch Protocol or JNLP is no exception. But sometimes you may have a hard time opening a JNLP file.

These files are used on a remote desktop client to launch applications from a hosted Web server. Java Web Start application, Java plug-in and similar programs run on JNLP files.

What is JNLP File?

JNLP or Java Network Launch Protocol files are program specific. Sometimes, your system may not correctly recognize JNLP files to run with the Java Web Start application.

In such cases, you will need to change your computer’s file association to properly open JNLP files with Java Web Start application.

How To Open The JNLP File

# 1) Install the latest version of JAVA

Changing your system’s file association is one way to successfully open a JNLP file. But before getting into this, you need to make sure you have proper Java programs on your system.

Look for a Java program on your system. If you can’t find it, it means it’s not installed yet. If so, download the latest version of Java on your system.

Do that

Visit the Java website .
Hit the Java download button.

You will be directed to the appropriate download page. Click Agree and launch the free download button.
This will start the download.

After the download is complete, click the installation launcher to complete the installation.

# 2) Changing the file association

Worried about how to open JNLP file ? As mentioned above, each type of file is associated with an application it runs on. JNLP files are executed by Java Web Start, and sometimes, it is possible that JNLP files may be associated with other applications, thus making them open incorrectly.

In such cases, you will need to change the file association on your computer so that JNLP files open with Java Web Start.

# 1) Windows 10

Open the Control Panel from the Start option.

Go to Programs and select Default Programs.
click on “Associate a file type or protocol with a program” .

From the list of extensions, select JNLP.
Select Change program.
If the correct Java application does not appear automatically, choose the More apps option.
Now look for another app on this PC.
Go to the Program Files (x86) folder.
Click on the Java folder.
Open the latest version of JRE you have.
Go to the bin folder.
Double-click the javaws.exe application.

Click OK and then Close.

This is the process to open the JNLP file in Windows 10.

# 2) On Mac

Go to the Finder.
Search for the JNLP file you want to open.

Right-click on the file.
Click Get Info.

On the information screen, go to Open with and click the arrow next to it.
From the application list, select Java Web Start.

If you can’t find it in the options, select Others and find it in the complete list of applications.
Select the right app and click Change All to apply the change to all JNLP files.
Click Continue.

JNLP files will now open on Mac without any problem.

3) Windows 8

From the right edge of the screen, swipe in, go to Search.

Enter Default Programs in the search bar.

Now click on the option – ‘Associate a file type or protocol with a program’ .

In the list of registered file types, find .JNLP.
Click on it once to highlight the file in the Extensions column.
Select Change program.

From the list of programs, select Java Web Start Launcher .

If it’s not in the options, click More options, then select Look for another app on this PC.
Double-click Local Disk (C :).

Double-click Program Files (x86) or Program Files, whichever you see.

Select the Java folder.
Select the most recent JRE folder.

Select trash.
Click on javaws.exe and press You open .

You will no longer have trouble opening JNLP files on Windows 8.

4) Old versions of Windows

Windows 7 and Vista

Select Control Panel from the Start menu.
Select Category from the View by option in the upper right corner of the control panel.

Go to the default programs option.
Click on the option “Make a file type always open in a specific program” .

Locate JNLP from the list of extensions in the Name column and click on it to select it.

Select the Edit option.
In the Open With window, select Browse.

The Open With dialog box will take you to the c: \ Program Files directory.
Now select the Java folder.

Double-click the last JRE folder.

Double-click the bin folder.

Now, double click on the javaws application.

Click OK and then Close.

You should be able to open the file now.

For Windows 2000 / XP

Go to the Start option.
From Settings, select Control Panel.

Go up Folder options and click on it.

In the window that opens, click on the tab Types of files .

Under the registered file types, locate JNLP and highlight the file by going to the Extensions column and clicking the JNLP file once.
Press the Change button.

In the Open With window, click Browse .
Locate the javaws.exe file from the Open With dialog box.

Double-click the Java folder in the C: \ Program Files folder.
Now double click on the JRE folder.

Find the bin folder inside it and double click on it.

Now select javaws.exe and click Open.

Click Ok to close the window.
Click Apply and click OK.

You will be able to open JNLP files now.

Configuring Chrome to open JNLP files

Launch Chrome.
Go to the website with a link to a JNLP file.
Download the file. You will be able to see the file in the window below.
Click the arrow beside and select “Always open files of this type” .
When Chrome asks you which program you want to open the file with, select ” Java Web Start Launcher ”.
If you don’t have Java Web Start Launcher, download and install it.

Now you can open JNLP files on Chrome.

Firefox displays JNLP files as text

Usually, as your browser or system is not configured properly to send JNLP files to Java Web Start, it will face some problems while opening the file. These problems could be the inability to open the file or the browser ending up displaying it as text. So, to open the JNLP file on Firefox, make the following changes.

# 1) On Linux

Start Firefox and press Alt.
Go to tools in Firefox.

Click on Options.

Scroll through the list and find the JNLP file.
To select Use Java Webstart Launcher in action.

# 2) OSX

Download the JNLP file.
Go to Finder and find the file.
Right click on it.
Select Get Info.
In Open with, select Java Web start.

If you can’t find it in the list, go to System, go to Library and click Core Services. Here you will find Java Web Start.
If it’s not there, go to Applications and click Utilities. There you can find Java Web Start.

Frequent questions

Q # 1) Why can’t I start JNLP?

Answer: make sure you have the latest version of Java. Also, check that your browser is not blocking the file of an unidentified developer as it could lead to blocking the RCSB-ProteinWorkshop file. jnlp. Always select the option “Open anyway” in these cases.

Q # 2) How to start Java Web Start launcher?

Answer: go to the control panel from the beginning and double click on the java icon. The Java Control Panel will start. Go to the General tab. From the Temporary Internet Files section, select View. Now, double click on the application you want to launch.

Q # 3) Am I getting a fatal initialization error while using Web Start?

Answer: i JNLP files must be run with javaws and if another application is your default java client, you will encounter this error. To start the file, either change the default browser preferences so that the JNLP application opens with javaws or go to the command line in the javaws viewer to force the JNLP file to ec = xecute with Java.

Conclusion

JNLP files may cause problems if they are not updated or if the file associations are confused. So, it’s easy to fix when you can’t open JNLP file.

However, try not to mess with them as a wrong click or keystroke in your program could be messed up. So, unless it is necessary, leave these files alone.