UPX File Extension

UPX file icon
Ultimate Packer For EXecutables Format
  • Developer
    Markus Oberhumer
  • Popularity
    3 (4 votes)

What is UPX file?

UPX is a file extension commonly associated with Ultimate Packer For EXecutables Format files. Markus Oberhumer defined the Ultimate Packer For EXecutables Format format standard. Files with UPX extension may be used by programs distributed for Windows platform. UPX file format, along with 134 other file formats, belongs to the Executable Files category. PeaZip is by far the most used program for working with UPX files. PeaZip software was developed by Giorgio Tani, and on its official website you may find more information about UPX files or the PeaZip software program.

Programs which support UPX file extension

Below is a table that list programs that support UPX files. UPX files can be encountered on all system platforms, including mobile, yet there is no guarantee each will properly support such files.

Programs that support UPX file

Windows Windows

How to open file with UPX extension?

There can be multiple causes why you have problems with opening UPX files on given system. What is important, all common issues related to files with UPX extension can be resolved by the users themselves. The process is quick and doesn’t involve an IT expert. The list below will guide you through the process of addressing the encountered problem.

Step 1. Install PeaZip software

The most common reason for such problems is the lack of proper applications that supports UPX files installed on the system. The solution to this problem is very simple. Download PeaZip and install it on your device. Above you will find a complete listing of programs that support UPX files, classified according to system platforms for which they are available. The safest method of downloading PeaZip installed is by going to developer’s website (Giorgio Tani) and downloading the software using provided links.

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

If the problems with opening UPX files still occur even after installing PeaZip, it is possible that you have an outdated version of the software. Check the developer’s website whether a newer version of PeaZip is available. It may also happen that software creators by updating their applications add compatibility with other, newer file formats. The reason that PeaZip cannot handle files with UPX may be that the software is outdated. The latest version of PeaZip should support all file formats that where compatible with older versions of the software.

Step 3. Set the default application to open UPX files to PeaZip

If you have the latest version of PeaZip installed and the problem persists, select it as the default program to be used to manage UPX on your device. The process of associating file formats with default application may differ in details depending on platform, but the basic procedure is very similar.

Selecting the first-choice application in Windows

  • Right-click the UPX file and choose Open with option
  • Next, select the Choose another app option and then using More apps open the list of available applications
  • The last step is to select Look for another app on this PC option supply the directory path to the folder where PeaZip is installed. Now all that is left is to confirm your choice by selecting Always use this app to open UPX files and clicking OK.

Selecting the first-choice application in Mac OS

  • Right-click the UPX file and select Information
  • Open the Open with section by clicking its name
  • Select PeaZip and click Change for all...
  • A message window should appear informing that This change will be applied to all files with UPX extension. By clicking Continue you confirm your selection.

Step 4. Verify that the UPX is not faulty

You closely followed the steps listed in points 1-3, but the problem is still present? You should check whether the file is a proper UPX file. It is probable that the file is corrupted and thus cannot be accessed.

1. The UPX may be infected with malware – make sure to scan it with an antivirus tool.

If the UPX is indeed infected, it is possible that the malware is blocking it from opening. Scan the UPX file as well as your computer for malware or viruses. If the UPX file is indeed infected follow the instructions below.

2. Check whether the file is corrupted or damaged

If you obtained the problematic UPX file from a third party, ask them to supply you with another copy. During the copy process of the file errors may occurred rendering the file incomplete or corrupted. This could be the source of encountered problems with the file. It could happen the the download process of file with UPX extension was interrupted and the file data is defective. Download the file again from the same source.

3. Check if the user that you are logged as has administrative privileges.

Some files require elevated access rights to open them. Log in using an administrative account and see If this solves the problem.

4. Check whether your system can handle PeaZip

If the system is under havy load, it may not be able to handle the program that you use to open files with UPX extension. In this case close the other applications.

5. Check if you have the latest updates to the operating system and drivers

Regularly updated system, drivers, and programs keep your computer secure. This may also prevent problems with Ultimate Packer For EXecutables Format files. It is possible that one of the available system or driver updates may solve the problems with UPX files affecting older versions of given software.

Do you want to help?

If you have additional information about the UPX 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 UPX file.

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