PACK File Extension

PACK file icon
Pack200 Packed Jar Format
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What is PACK file?

A .PACK file is a compressed binary Jar file that is created by the Pack200 utility belonging to Java 1.5.0 software program. The PACK file containing the jar files is compressed with a compression rate of 60%, and the compressed jar files are retrieved using the Oracle Java web start clients. The retrieved and unpacked jar files are used by the Java programs. While the compressed jar files are commonly available as .PACK.GZ file, the PACK files are also associated with .jar.pack extension. The main application that uses the PACK file, Oracle Java web start application, is supported on Windows, Linux, and MAC OS.

Programs which support PACK file extension

The list that follows enumerates programs compatible with PACK files, divided into 3 categories based on operating system on which they are available. Files with PACK extension, just like any other file formats, can be found on any operating system. The files in question may be transferred to other devices, be it mobile or stationary, yet not all systems may be capable of properly handling such files.

Programs that support PACK file

Updated: 04/26/2020

How to open file with PACK extension?

There can be multiple causes why you have problems with opening PACK files on given system. What is important, all common issues related to files with PACK extension can be resolved by the users themselves. The process is quick and doesn’t involve an IT expert. The following is a list of guidelines that will help you identify and solve file-related problems.

Step 1. Download and install Pax200

Install software to open PACK file The main and most frequent cause precluding users form opening PACK files is that no program that can handle PACK files is installed on user’s system. The most obvious solution is to download and install Pax200 or one to the listed programs: Java Web Start. The full list of programs grouped by operating systems can be found above. If you want to download Pax200 installer in the most secured manner, we suggest you visit website and download from their official repositories.

Step 2. Verify the you have the latest version of Pax200

Update software that support file extension PACKIf you already have Pax200 installed on your systems and PACK files are still not opened properly, check if you have the latest version of the software. Software developers may implement support for more modern file formats in updated versions of their products. The reason that Pax200 cannot handle files with PACK may be that the software is outdated. The most recent version of Pax200 is backward compatible and can handle file formats supported by older versions of the software.

Step 3. Associate Pack200 Packed Jar Format files with Pax200

If the issue has not been solved in the previous step, you should associate PACK files with latest version of Pax200 you have installed on your device. The method is quite simple and varies little across operating systems.

Associate software with PACK file on Windows

The procedure to change the default program in Windows

  • Choose the Open with entry from the file menu accessed by right-mouse clicking on the PACK file
  • Next, select the Choose another app option and then using More apps open the list of available applications
  • To finalize the process, select Look for another app on this PC entry and using the file explorer select the Pax200 installation folder. Confirm by checking Always use this app to open PACK files box and clicking OK button.
Associate software with PACK file on Mac

The procedure to change the default program in Mac OS

  • From the drop-down menu, accessed by clicking the file with PACK extension, select Information
  • Proceed to the Open with section. If its closed, click the title to access available options
  • Select the appropriate software and save your settings by clicking Change all
  • Finally, a This change will be applied to all files with PACK extension message should pop-up. Click Continue button in order to confirm your choice.

Step 4. Ensure that the PACK file is complete and free of errors

Should the problem still occur after following steps 1-3, check if the PACK file is valid. Problems with opening the file may arise due to various reasons.

Check PACK file for viruses
1. Verify that the PACK in question is not infected with a computer virus

If the file is infected, the malware that resides in the PACK file hinders attempts to open it. Immediately scan the file using an antivirus tool or scan the whole system to ensure the whole system is safe. If the PACK file is indeed infected follow the instructions below.

2. Check whether the file is corrupted or damaged

If you obtained the problematic PACK file from a third party, ask them to supply you with another copy. The file might have been copied erroneously and the data lost integrity, which precludes from accessing the file. When downloading the file with PACK extension from the internet an error may occurred resulting in incomplete file. Try downloading the file again.

3. Ensure that you have appropriate access rights

There is a possibility that the file in question can only be accessed by users with sufficient system privileges. Log in using an administrative account and see If this solves the problem.

4. Verify that your device fulfills the requirements to be able to open Pax200

If the systems has insufficient resources to open PACK files, try closing all currently running applications and try again.

5. Ensure that you have the latest drivers and system updates and patches installed

Up-to-date system and drivers not only makes your computer more secure, but also may solve problems with Pack200 Packed Jar Format file. Outdated drivers or software may have caused the inability to use a peripheral device needed to handle PACK files.

Do you want to help?

If you have additional information about the PACK file, we will be grateful if you share it with our users. To do this, use the form here and send us your information on PACK file.

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