OPAX File Extension

Microsoft Office Customization Tool (OCT) Standard Settings

File Type opax
Developer Microsoft Corporation
Popularity
4.5 (40 votes)
Application Office Customization Tool
Category Settings Files
Format Text

What is a OPAX file?

Files with the OPAX extension are specifically tied to Microsoft Office Customization Tool (OCT) Standard Settings, a Settings Files type, and there are 1190 files in this category.

The Microsoft Office Customization Tool (OCT) Standard Settings (OPAX) was developed by Microsoft, which created file format and 242 programs to work with them.

OPAX file support extends to various operating systems, including Windows. To open a OPAX file, you can choose from 2 programs such as Office Customization Tool and Microsoft Office.

Programs that support OPAX files

Windows ²

Windows

How to open a OPAX file?

If you cannot open a OPAX file, it is most often due to missing software. Select a program from the list according to your operating system. Then go to the official website of the program developer, download it, and install it on your device.

Thanks to their popularity, Office Customization Tool and Microsoft Office are often the go-to programs for managing OPAX files. If you need the newest version of Office Customization Tool, just access the Microsoft website. From there you can download the installer compatible with all systems.

Once Office Customization Tool is installed, the OS should configure it as the default tool for opening OPAX files.

Make Office Customization Tool the default OPAX viewer

Change the default app to open files on Mac

Right click or use Control + Left Click on the desired OPAX file to access a dropdown menu of actions;
Choose "Open in Application" and click "Other";
Towards the bottom of the window, find the "Enable" menu, which is already set to the default option, "Recommended Programs";
In this menu, select "All Programs" and search for Office Customization Tool. Check the box next to "Always open in app" to make it the default option.

Change a default app in Windows

Start by right-clicking on your OPAX file, then select the "Open with" option and choose "Choose another app" from the menu that appears;
Inside the popup window, scroll through the list of applications and specifically choose Office Customization Tool as the application to associate with your OPAX file;
Check the "Always use this app" checkbox and click "OK".

Finding answers to OPAX file problems

If OPAX files are giving you trouble, small modifications to your software can help. Check out the troubleshooting tips below to fix these issues.

What can lead to sudden Office Customization Tool crashes?

Insufficient updates for Microsoft products can cause Office Customization Tool to crash. Be sure to regularly install the latest software updates.

A computer restart is often the key to solving numerous common problems. That’s why, it is recommended to restart the computer before making any changes to the software settings.

What is the recommended approach to repair a damaged OPAX file?

Use a recovery program to open the damaged OPAX file, and in the menu, click "Repair" to start the repair operation. Wait for the recovery process to finish as it will automatically restore the damaged settings files.

What are the ways to check if my OPAX file is damaged?

Characteristics of corrupted OPAX settings files can include:

The file encounters problems during the opening process or shows error indications;
Editing the archive in Office Customization Tool is hampered by poor overall performance;
The file causes Office Customization Tool or other software to hang or crash during various operations;
An unexplained increase in the size of the OPAX file;
Actions performed on the file result in the appearance of error notifications;

How to edit a OPAX file?

To modify OPAX files, you need to install special software that makes it possible to open and edit settings files. Online OPAX editors are more restricted compared to software designed for Microsoft Office Customization Tool (OCT) Standard Settings.

Best OPAX editors 2026

According to these factors, we have compiled a list of available OPAX editors.

OPAX Editor Software	Developer	Platforms	Overall Rating
Office Customization Tool	Microsoft	Windows	4.7 out of 5 (40 reviews)

‹ OPENBSD | OPAL ›