Here’s Everything You Should Know About DMS Files

DMS System Digital Rights Management

You double-clicked on a .DMS file, so now you’re seeing the “Choose a program to open the file” message. Of course, you can choose to open the file with a number of programs, but expect the contents to be all garbled. Not to worry, though, we have you covered!

What Is a DMS File?

A Disk Masher (.DMG) image file or .DMG file is a compressed file type that is encoded using specifications similar to that of an Amiga disk image file. It was initially used to archive and compress data on floppy disks.

This file format is copyright-protected. However, it has been pirated widely, so it can be used in various demo scenes in the software development industry. As a result, issues and bugs in the compression algorithm arise.

Before we discuss these issues and bugs, let’s first discuss how to properly open a DMS file.

Expert Tip: For smoother PC performance, consider using a PC optimization tool. It handles junk files, incorrect settings, and harmful apps. Make sure it's right for your system, and always check the EULA and Privacy Policy.

Free Scan for PC Issues
Compatible with: Windows 10/11, Windows 7, Windows 8

Special offer. About Outbyte, uninstall instructions, EULA, Privacy Policy.

How Do You Open a DMS File on a Windows Device?

To open a DMS file on a Windows device, you need to use suitable software like Amiga Disk Masher. Otherwise, you will receive a message asking you how you want to open this file.

If you cannot open a DMS file properly, right-click on it and select Open With. Next, choose an application or program that supports the file.

Here are some programs that open and support DMS files:

1. Amiga Disk Masher

Amiga Disk Masher is a popular program that can create and uncompress .DMS files. It is popular among Bulletin Board System (BBS) users and is mainly used for Amiga emulation.


Build Your Own Net Dream (BYOND) is a platform that is widely used for publishing, forging, and playing multimedia, multi-user, networked games.

Here’s a handy hack you can apply, so you need not be asked every single time to select what program or software to use to open a DMS file. Right-click on any DMS file. Select Open With. Now, choose the software you want and check the box next to the Always use this app to open .dms files option.

How to Open DMS file on iMac

Now, if you are using an iMac or other iOS devices, the way to open a DMS file is slightly different. But it remains easy. As long as you have the right programs installed on your iMac or iOS device, then you should be able to open the DMS file smoothly.

To open a DMS file on your Apple device, you should first find out what Apple software supports DMS files.

As mentioned above, Amiga DiskMasher and BYOND are two popular software for Windows that support DMS files. But for Apple devices, your options are The Unarchiver, Cloanto Amiga Forever, and MaxUAE.

So what you should do is download any of the three software packages and install them on your Apple device. Once you have one installed, opening a DMS file on your iMac will be easier. You just need to right-click on the file and select the program you recently installed from the list of options.

If this does not work, you might need to seek help from the support team of the software developer. They may recommend ways on how you can properly open the DMS file.

More About DMS Files

Now that you know how to open DMS files on Windows or Apple devices, you might want to find out more information about it.

If you are using a Windows device, simply right-click on the file and navigate to Properties. Then, click Type of File. All the information about the DMS file will now open in a pop-up window.

For iMacs, right-click on the file and go to Properties. Next, click More Info and select Kind. You should now see more information about the DMS file.

How to Solve Issues with DMS Files

Problems with DMS files are almost inevitable. After all, many developers attempt to pirate it, resulting in a confusing algorithm that computers don’t understand.

To fix problems with DMS files, here are some solutions we suggest you should try:

1. Run the File Using the Correct Software or Application.

Sometimes, problems with DMS files occur because the application you are using cannot read them. Therefore, you have to ensure you are running the correct application.

For Windows devices, you can use Amiga Disk Masher or BYOND. Apple device owners, on the other hand, can use The Unarchiever, Cloanto Amiga Forever, or MaxUAE.

2. Update the Application or Software You Are Using to Open Compressed Files.

If you have the correct application installed but still cannot open the DMS file, it is likely because you are using an outdated version. Only the latest versions of the software support DMS file formats.

To update your software, go to the developer’s website and search for an available update.

3. Make Sure Your DMS File Is Not Corrupt.

Still cannot open the DMS file? You might want to check if it is corrupted or virus-infected. To do that, install a reliable antivirus software on your computer and download the file again from the official manufacturer’s site.

Once the antivirus software detects that something’s wrong with the file, it will notify you and seek your confirmation on whether or not to continue the download.

4. Scan and Clean Your Computer.

Oftentimes, a quick scan can resolve any problems you have on your computer. If you are a Windows user, you can use the Windows Defender utility to run the scan. But if your computer is running on macOS, you can scan your system with the built-in Disk Utility tool.

However, if you want to perform a more efficient system scan, you can use a third-party PC cleaning tool. Within minutes, a reliable and trustworthy Windows or Mac cleaning tool can already pinpoint possible threats that can trigger future issues.


DMS files may seem alien to most Windows or Mac users. But it’s probably worth learning about these files, so you know what to do with them in case you encounter one in the future. Hopefully, this short article has provided you with enough information you need to know about these files.

In case we missed something important about DMS files, do let us know below!

Give us some love and rate our post!
[Total: 0 Average: 0]
Notify of
Inline Feedbacks
View all comments