How do you access older volumes, whose DRM issues stop access?

[#1]

I have been a user of digital editions for some ten years, and as a university professor, I cannot lose my books because of the change of hardware.My original connection to the service was through Palm and then through MicroSoft and now Apple, and I find that three volumes are no longer accessible because of DRM issues.They are mine, paid for and used in an earlier iteration of my Digital Editions account. How do I recover my books?

Crm: 07558000000976

Books 9780802779243_epub.V5.Epub

9781429979665_epub.V6.Epub

Dreaming In Chinese.Epub

[#2]

I have been a user of digital editions for some ten years, and as a university professor, I cannot lose my books because of the change of hardware.My original connection to the service was through Palm and then through MicroSoft and now Apple, and I find that three volumes are no longer accessible because of DRM issues.They are mine, paid for and used in an earlier iteration of my Digital Editions account. How do I recover my books?

Crm: 07558000000976

Books 9780802779243_epub.V5.Epub

9781429979665_epub.V6.Epub

Dreaming In Chinese.Epub