X File Extension
DirectX Model Format
- File Type x
- Developer Microsoft
- Popularity
- Application Flex
- Category Developer Files
- Format Text
What is a X file?
DirectX Model Format, identified by the X extension, is a Developer Files type and includes 1166 files.
The DirectX Model Format (X) was developed by Microsoft, which created file format and 242 programs to work with them.
X file support extends to various operating systems, including Windows. To open a X file, you can use software like Flex.
How to open a X file?
If you cannot open a X 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.
The most commonly used program for managing X files is Flex. If you want the most recent release of Flex, head over to the Flex Project site and download the version designed to run on all platforms.
After installation, your operating system should automatically open X files with Flex.
Setting Flex as default X viewer
Changing Default Programs in Windows
- Right click on your X file, then select "Open with" and click "Choose another application";
- Choose Flex from the available applications listed in the pop-up window to set it as the default application to open your X file;
- Be sure to check the "Always use this app" checkbox, and then click "OK" to confirm your selection.
Change the default app for a file type in Mac
- Initiate a right click or use Control + left click on the desired X file to open a menu where you can select various actions;
- Select "Open in application" and click "Other";
- Next, at the bottom of the window, you will see the "Enable" menu, in which "Recommended Programs" is selected by default;
- In this menu, select "All Programs", then find Flex and check the box next to "Always open in the application."
Tips and tricks to solve problems with X files
There are some common issues with X files that can be resolved easily by making minor adjustments to your software. Below, you’ll find these issues along with practical troubleshooting tips.
What Causes Flex to Crash Frequently?
The likely cause of Flex crashing is lack of software updates. Install the latest updates available for Flex Project products.
Restarting your computer is an essential troubleshooting step that can resolve many common problems. It is recommended to restart your computer before making any changes to the software settings.
How can I restore a damaged X file?
Open the corrupted X file in a recovery program and select the "Repair" menu item. Wait for the recovery process to finish, as it will automatically repair damaged developer files.
How do I know if my X file is corrupted?
Common indications of damaged X developer files are:
- The file shows errors when trying to open it or does not open completely;
- Editing the archive in Flex results in slow or unresponsive behavior;
- Opening or processing the file in Flex or other programs causes instability or crashes in the program;
- Unexpected expansion of the total size of the X file;
- Error messages appear while working with the file;
How to edit a X file?
To edit X files, it is essential to install software that supports not only viewing but also editing the developer files. Online X editors provide limited functionality compared to full-featured software for DirectX Model Format.
List of Top X editors 2026
Based on these criteria, we have prepared a list of available X editors.
| X Editor Software | Developer | Platforms | Overall Rating |
|---|---|---|---|
| Flex | Flex Project | Windows | 4.6 out of 5 (38 reviews) |
Convert to and from X
If working with a X file is challenging, one solution is to convert it to formats like OBJ, STP, DAE, 3DS, MAX or other supported formats.
Keep in mind that converting a X file may introduce some limitations, but the original format can often be restored.