MST File Extension
Windows Installer Setup Transform Format
- File Type mst
- Developer Microsoft
- Popularity
- Application Windows Installer
- Category Developer Files, Blocked Email Attachment Files
What is a MST file?
Windows Installer Setup Transform Format works with the MST file extension and is classified under Developer Files and Blocked Email Attachment Files, with a total of 1242 files.
With the creation of the Windows Installer Setup Transform Format (MST), Microsoft introduced file format along with 242 programs built for their use.
MST files are compatible with various operating systems, including Windows, Mac OS and Linux. You can open a MST file using one of 8 programs, for example Windows Installer, Atom and PSPad.
Programs that support MST files
How to open a MST file?
The most common reason why a MST file cannot be opened is the absence of required software. To fix this, select a compatible program from the list. Then visit the official developer website via the provided link, download the program, and install it on your system.
Windows Installer, Atom and PSPad are among the most widely used programs for handling MST files. If you wish to install the latest release of Windows Installer, visit the official Microsoft portal and download the edition that works on any operating system.
Following installation, MST files should be automatically opened with Windows Installer.
Set Windows Installer as the default MST application
Change the default app that opens a file on Mac
- Right-click or use Control + Left-click on the desired MST file to open a menu where you can choose from multiple actions;
- Choose "Open in Application" and click "Other";
- Look at the bottom of the window, where you will see the "Enable" menu. "Recommended Programs" will be selected as the default option;
- Within this menu select "All Programs" and navigate to Windows Installer. Check the box next to "Always open in app" to make sure it’s the default option.
Change default programs in Windows
- Start the process by right-clicking on your MST file and selecting "Open With". From there, click "Choose another app" to continue;
- From the options listed in the pop-up window, specifically choose Windows Installer as the application to handle your MST file;
- Be sure to check the "Always use this app" checkbox and click "OK" to save your preference.
How to edit a MST file?
To modify MST files, it is necessary to install dedicated software that lets you open and edit developer files. Online MST editors generally offer fewer tools compared to programs designed for Windows Installer Setup Transform Format.
Best MST Editor Software in 2026
Taking into account the provided details, we have prepared a list of MST editors that match your needs.
| MST Editor Software | Developer | Platforms | Overall Rating |
|---|---|---|---|
| PSPad | Jan Fiala | Windows | 4.7 out of 5 (41 review) |
| Notepad++ | Notepad++ Team | Windows | 4.6 out of 5 (37 reviews) |
| Sublime Text | Sublime HQ Pty | Windows, Mac OS, Linux | 4.6 out of 5 (39 reviews) |
| Microsoft Windows Software Development Kit | Microsoft | Windows | 4.3 out of 5 (41 review) |
| Atom | - | Windows, Mac OS, Linux | 4.1 out of 5 (36 reviews) |
Convert files to and from MST
If a MST file is cumbersome, converting it to formats such as PDF or other supported types can make it easier to manage.
It is important to understand that converting a MST file might limit certain functions, but this conversion is usually reversible.
Convert MST to other file formats
Troubleshooting guide for MST file complications
When issues arise with MST files, they can generally be fixed with small software tweaks. Use the troubleshooting tips below to help resolve them.
What are the possible solutions to recover a corrupt MST file?
Start a recovery program, open the damaged MST file and then select the "Repair" menu item to start the repair procedure. Wait for the recovery process to finish, allowing automatic repair of damaged developer files.
How can I confirm if my MST file has been damaged?
The signs of corrupted MST developer files can manifest as:
- The file shows slow performance when edited in Microsoft Windows Software Development Kit;
- The file stops responding or freezes in Windows Installer or other programs;
- The file does not respond or shows errors when opening it;
- Unexplained MST file size inflation;
- The file operation is accompanied by the display of error messages;
What are the possible causes of Windows Installer crashing?
Lack of regular software updates can cause Windows Installer to crash. Make sure you have installed the latest updates for Microsoft products.
Restarting your computer is a crucial troubleshooting measure that can alleviate numerous common problems. Therefore, it is advisable to restart your computer before modifying any settings related to the software.