Updated : July 10th, 2024
ePub DRM Removal quickly and easily remove Adobe ebook ADEPT DRM protection. it supports ePub/PDF drm ebook that was opened in Adobe digital editions, create new nodrm file without DRM limitation. user can view ePub ebook on iPad, Sony Reader or other device, convert to mobi format to read in Kindle ereader, convert to PDF format to print Digital Edition ebook.
To remove Adobe ebook drm, you need to install Adobe digital editions, and download ebook in Digital editions, you also can open epub file that download in Sony library application or Kobo reader application.
check “Re-build key file” to create new file, then try again.
if new key file doesn’t work, you still get same error, then de-authorized in digital editions and authorized again, do as follow:
EPUB is a free and open e-book standard by the International Digital Publishing Forum (IDPF). Files have the extension .epub.
EPUB is designed for reflowable content, meaning that the text display can be optimized for the particular display device used by the reader of the EPUB-formatted book. The format is meant to function as a single format that publishers and conversion houses can use in-house, as well as for distribution and sale.
An EPUB file can optionally contain DRM as an additional layer, but it is not required by the specifications. In addition, the specification does not name any particular DRM system to use, so publishers can choose a DRM scheme to their liking. However, future versions of EPUB (specifically OCF) may specify a format for DRM.
You have purchased DRM-protected epub eBook, then you have probably discovered how annoyingly restrictive DRM technology is. You can try our software that removes epub DRM easily and produces DRM-free ePub ebook that you can enjoy on practically any capable e-reader device.
Vitalsource provide web access to user Bookshelf, user can read book in any browser without app installed, visit Vitalsource.com, click Bookshelf in page, 
Login account and goto bookshelf page, click book title to read 
if unauthenticated message show up, you should contact with Vitalsource to ask help, vitalsouce will resolve this problem.
PDF is popular file format but not support very well by Kindle device and Kindle App, If you want to read pdf files on your kindle, then you should convert pdf to azw, azw3, mobi format and so on. it is better experience to convert pdf to kindle format (.mobi .azw) format before you read pdf in Kindle device.
Before converting pdf to azw kindle, you should make user pdf doesn’t have password protection.
1) Download and install eBook Converter Bundle
eBook Converter Bundle is tools to convert epub/azw/pdf ebook to epub/mobi/rtf/text format file, support eBooks purchased from Kindle, Nook, Google Play, Sony, Kobo and other online eBook stores.
2) Drag pdf file into converter file list, or click Add Files button to add pdf file into list, mark checkbox. 
3) Change output format to Kindle mobi format at “Output Options” tab at bottom.
4) Click Convert button to start conversion, it will takes minutes to finish job, new .mobi file save in output folder, click Open output folder to find new .mobi file.
