.DMS File Extension

A DMS file is a compressed Amiga disk image created using Amiga's Disk Masher System (DMS). It contains data intended for use with an Amiga computer. DMS files were originally used to transfer data among Amiga users via physical floppy disks, but are now most often used to share Amiga games, programs, and other files online, for use with Amiga emulators such as Amiga Forever.

The Amiga was created by Commodore International and was one of the earliest PCs to support advanced graphics, sound, and video. Its superior multimedia capabilities made it quite popular among gamers, music enthusiasts, video producers, and other creatives. However, as other companies released computers and game consoles that matched or surpassed the Amiga's capabilities, the Amiga faded from the PC market.

Many modern decompression programs do not support the DMS format, so you might have to download a program such as The Unarchiver (Mac) or WinFellow (Windows) if you want to view the files contained within a DMS archive.

To actually open and use the files contained within a DMS archive, you will have to download an Amiga emulator such as Amiga Forever.

A DMS file is a script file (i.e. "connect.dms") run by Dream Seeker, a client for playing online games. It was created by Dream Maker, part of the BYOND (Build Your Own Net Dream) suite of programs.

A DMS file is a file that has been downloaded and renamed by the Apple Safari web browser or the Apple Mail email client. It contains the contents of a file that did not have a file extension or was erroneously renamed when downloaded. The .dms extension is a result of a bug in Safari and Mail.

You most likely will encounter this type of DMS file only if you download a file that does not have a file extension in macOS with Safari or Mail. In some cases, Safari or Mail may also replace a valid extension with .dms or may append the .dms extension onto a file extension. For example, sample.pdf may become sample.dms or sample.pdf.dms when downloaded with Safari or Mail.

The bug is specific to Macs and has been reported across multiple versions of Mac operating systems, with some issues dating back to the early 2000s. While Safari and Mail are the typical perpetrators, the .dms renaming may also occur with other web browsers and programs.

To open a DMS file, rename the .dms extension with the appropriate extension for the file type. For example, if you know you downloaded an .XLSX file that was renamed with the .dms extension, click on the extension to highlight it and change it back to .xlsx. Then, you can open the file with a program that supports XLSX files.