"How to open ACSM file on iPhone? What is the app to read acsm files - these are ebooks. I've tried adobe reader, freda, kindle and mediabook and does not work. Thanks."  Asked by Ana on Microsoft Community.

We often download an .ACSM file after purchasing an eBook online, but it's not the eBook file. Here in this guide we will tell you what ACSM file is, how to open ACSM file on different devices, and how to convert ACSM to EPUB, PDF and other eBook formats.

Part 1: Introduction to ACSM File

Used by Adobe Digital Editions to activate and download Adobe DRM protected content, a file with the .ACSM file extension is an Adobe Content Server Message file. It should be noted that ACSM file actually are not eBook files like EPUB or PDF file, which could be opened by various eBook readers like Adobe Digital Editions, Kobo, Kindle, etc.

Log in Adobe Digital Editions app

The ACSM file is actually nothing but information that is used to communicate with Adobe's servers to let the server authorize the books you've purchased to be downloadable on computer through Adobe Digital Editions. You can then read the purchased books on the same software on any of your devices with the same account. You can't find and books built in these ACSM files.

Part 2: How to Open ACSM Files on Different Devices

Then, how to open ACSM file on iPhone, iPad, Android, Nexus and Mac computer? From the above introduction we would know that ACSM files could only be read by Adobe Digital Editions software. You could use Adobe Digital Editions to open ACSM files on Windows, macOS, Android, and iOS devices. When the book is downloaded on one device, it can be downloaded to any other device that's using Adobe Digital Editions under that same user ID.

To connect your eBook vender account to Adobe Digital Editions, you need to go into "Help > Authorize Computer..." menu option in Adobe Digital Editions. This is the only way you can be sure that your books are available on your other devices for you to download again on other devices even they are deleted. You therefore don't need to buy the book again.

But this also means that you could only read Adobe DRM protected data you've authorized to through the same account on different devices like computer or mobile eBook readers.

Part 3: How to Convert ACSM to other eBook Formats with Prof. DRM

Due to the fact that an ACSM file is not an e-book, you can’t actually convert ACSM file to eBook format like ePub, PDF, etc. even though the ACSM file shows you how to download a read eBook file, which might be in PDF or ePub with DRM protection.

If you just want to convert the text information on how to download a read eBook file in ACSM file to ePub or PDF file, you could follow the below steps:

1. Install Adobe Digital Editions (ADE).

2. Register with your Adobe account.

3. Drag the .ACSM file into ADE.

4. ADE would convert ACSM to EPUB.

5. Use EPUB DRM Removal to remove DRM from the EPUB.

Adobe Digital Editions doesn’t provide DRM removal feature for you. To remove the DRM protection and convert ACSM file to ePub or PDF eBook format, you can turn to Leawo Prof. DRM, a professional DRM removal program that could remove DRM protection upon Adobe Digital Editions eBooks and then convert Adobe Digital Editions eBooks to DRM-free ePub, PDF, Mobi, and other formats.

Download and install Leawo Prof. DRM. Follow the below steps to learn how to convert ACSM to ePub or other eBook formats.

Step 1: Log in Adobe Digital Editions

Launch Adobe Digital Edition software on your computer and log in with your account. You will then see all eBooks you’ve downloaded on your Adobe Digital Editions.

Log in Adobe Digital Editions app

Step 2: Add eBooks from Adobe Digital Editions

Since you've turned the ACSM files into books on your ADE as mentioned above, now you could take ACSM files as DRM protected books for converting. Launch Leawo Prof. DRM and then click the "Add File" button on the interface. On the left sidebar, you could see an "Adobe" tab, which includes all eBooks on your ADE. Choose the ACSM files and other books you would like to convert.

Add Adobe eBooks

Step 3: Set output format

Click the pencil icon in each loaded eBook title and then choose output format from ePub, Mobi, TXT, etc. For time saving, check “Apply to all eBook files” option.

Set output format

Step 4: Set output directory

Then, move mouse to the bottom and set output directory in the “Output” box.

Set output directory