The File Extensions Database

.ACSM File Extension

  • Developer by: Adobe Systems
  • Category: eBook Files
  • Format: Binary

What is an .ACSM file?

.ACSM is Adobe Content Server Message File

An ACSM file is a message file served by the Adobe Content Server to Adobe Digital Editions, a program used to manage and read eBooks as well as other digital publications. It contains data to activate and download an eBook but does not contain the eBook itself. ACSM files are used to authorize, legally download, and read purchased eBooks in Digital Editions.

Most Digital Editions users will not encounter an ACSM file. If you do find an ACSM file, it most likely means that the download of your book was interrupted. You can double-click the ACSM file to resume the download and open the file in Digital Editions. The ACSM file will be located wherever your browser saves downloaded files.

NOTE: Even if you have a different eReader software other than Digital Editions, such as Kobo Desktop, you may still receive an ACSM file when downloading an eBook. However, you still must install Adobe Digital Editions to download the eBook and then it can be read and transferred to your eReader device.

Programs that open Adobe Content Server Message File
Adobe Digital Editions
Adobe Digital Editions

How to solve problems with ACSM files

  • Associate the ACSM file extension with the correct application. On :
    Windows: Right click on any ACSM file and then click "Open with" > "Choose another app". Now select another program and check the box "Always use this app to open *.ACSM files". Mac: Right click (or Ctrl-click) the ACSM file, then click "Open with" > "Other...". Then choose another program and check the "Always Open With" box. Linux: Right click on the file, and select "Open with" and choose another program. iPhone: Tap the file. If you do not see an app to open the file, then tap Share "Share" and choose an app. Alternatively, save the file. Then open the Files app Files app. There long-press on the file, then release your finger. You will see a black menu bar. Then tap "Share" and select an app. Android: Tap the Settings icon on your smartphone, then tap on the Apps section. There tap the Options icon in the top right-hand corner of the screen to change the default apps.
  • Update your software that should actually open .ACSM is Adobe Content Server Message File. Because only the current version supports the latest ACSM file format. Search, therefore, e.g. on the Adobe Systems manufacturer website after an available .ACSM is Adobe Content Server Message File update.
  • To make sure that your ACSM file is not corrupted or virus-infected, get the file again and scan it with antivirus software.