If you are receiving the Adobe Digital Editions error “Unable to download. Error getting License. License Server Communication Problem: E_ADEPT_NO_TOKEN” when downloading an ebook from Ebook Central, contact Ebook Technical Support (ebooksupport@proquest.com, or Submit a Case) to report the error. Provide Technical Support with the Ebook Central URL for the ebook, the title of the ebook, and a screen shot of the error message. 

Other Adobe Digital Editions errors might be resolved by deauthorizing and reauthorizing Adobe Digital Editions