Using Calibre and DeDRM Plug-In to remove Adobe DRM from Google Play .ascm ePUB files

I previously wrote EPUB and DeDRM: Why Google Play Store is the best eBookStore for iBooks fans. (Bonus: Fixing Adobe Digital Edition crash.), but my efforts to put the books I own on my personal device were frustrated when it turned out all of my Google Play books were DRM free. So I could easily put the ePUBs in Google Drive, upload to Google Play and drop them into iTunes for use on my iPhone.

Today I purchased a genuine Google Play Adobe Editions DRMd book. I was able to remove the Adobe DRM and open it in iBooks on my iPhone. So it's doable - barely. I fear, however, that my app.net friends who think this is an easy solution to eBook DRM problems are operating on a higher plain than I. DRM removal is not the answer to flat (soon falling?) eBook sales. iTunes music style DRM (signed files) is the answer.

I'm not sure I can quite recreate all the steps, but these tips may help Mountain Lion users. Use them while you read and reread Apprentice Alf's guide. 

Downloads

You need to download the following apps and install the first two.

1. Adobe Digital Edition
2. Calibre
3. The limelinx tools (includes the DeDRM app but, most importantly, the DeDRM_calibre plugin)

Configuration

1. Download your ePub from Google Apps. This process is very cryptic (I think Google wants us to stop downloading these.) Mouseover your book in Play, look for a strange faint dashed line icon, click it to get the download option. You will download a .ascm file.
2. Launch Adobe Digital Edition and register yourself with Adobe. Open your .ascm file in ADE, observe that an ePub file is now saved to Documents/Digital Editions. Note that carefully.
3. Launch Calibre and then carefully follow the directions for installing  DeDRM_plugin.zip into Calibre. Note that Calibre has changed a bit since the directions were written so some interpretation may be needed.
4. The directions say: "On Macintosh and Windows systems no customization is required for ebooks from Kindle for Mac/PC or Adobe Digital Editions (ADE), provided that calibre is run on the same computer and user account as the installation of Kindle for Mac/PC or ADE to which the books were downloaded. The default key is found and stored in the preferences automatically. "  This did not work for me. I had to follow the configuration steps, which are cryptic. I clicked on DeDRM then clicked the customize button the configuration for "Adobe Digital Editions eBooks", then click on the green + to get "default_key". Ignore "Import Existing Keyfiles". Then restart Calibre.

Import book into Calibre, save ePUB to desktop.

1. Now, using Calibre, import the ePub file saved in Documents/Digital Editions.
2. You should be able to to Save Only ePub format to disk. The ePUB produced at that point is DRM free (or was in my case).

Using DeDRM app

 

Prior to using Calibre I'd tried DeDRM.app unsuccessfully; it didn't have a key (".der file") and coulndn't find one. After I'd gotten the Calibre process working I tried DeDRM again and it had the "default_key". I ran it again the Documents/Digital Editions ePub and it told me the DRM was removed. This is a much easier process than using Calibre; perhaps there is a shortcut to get directly to this step. Going forward I expect to use DeDRM.app.

 

Incidentally, the Alf site warns that commercial "DeDRM" apps are wrapped copies of the DeDRM code. I believe that's true.

 

Update 3/27/2014:After I got the default_key working I can simply use DeDRM to remove ePUB DRM. The configuration process creates a .der file that is stored in /Users/YourUserName/Library/Preferences/com.apprenticealf.dedrm. That .der file can be added to a new DeDrm.app install through simple setup — it’s the output of the complex process described above.