After two days of grief getting messages on my e-reader telling me: "Because you previously deauthorized your eReader, you need to re-import the book using Adobe Digital Editions (ADE). Please visit help.kobo.com for more information", and several times following and failing with the earlier recovery steps (deleting problem books, deauthorizing ADE, getting new books, re-uploading books from the library, etc. etc.) that have always worked before, plus about an hour yesterday on instant messaging with Kobo support staff, I am happy to report that my Kobo Glo HD is finally recognizing that it is indeed authorized to read ADE files. Kobo support staff recommended that I downgrade from the latest version of ADE to ADE 3.0. But I’m not at all comfortable with that.   These are the laborious steps I followed:   1. Deleted the books from the Kobo 2. Deauthorized ADE with the eReader (clicked on e-reader to go to the gearshift icon to the right in the side menu) 3. Deauthorized ADE with the computer (from the Help Menu at the top) 4. Using "recently added" section of ADE, deleted all the copies of the problem books from ADE 5. Deleted the books from the computer (usually there is a downloads file and a my adobe digital editions file) deleted the books from both 6. Closed ADE 7. Disconnected the Kobo from the computer (after this was done, seeing a message saying the the e-reader was not authorized to read ADE files) Duh. I know! This is the reason for this ridiculous list! 8. Turned off the computer and walked away (errm... stomped away). 9. About 12 hours later, turned on the computer, opened ADE 4.5.10.148 and authorized it with the computer, then, after going to the public library website to get a new copy of it, downloaded one of the problem books to ADE. 10. Closed ADE 11. Connected e-reader to the computer and ran Kobo Desktop to check for updates and re-sync the e-reader. 12. Opened ADE and authorized e-reader, leaving e-reader connected to the computer. 13. Closed ADE. 14. Opened ADE and erased authorization for the computer, but left the e-reader authorized. 15. Went to the public library website and downloaded a NEW book as well as the rest of the new copies of what were the problem books from the public library to the computer- it seems to be essential to get one that has not been previously borrowed. Uploaded the new book to ADE. As usual, Adobe PROMPTED me for authorization. (If it doesn't, I go back to "help" at the top and reauthorize ADE.) 16. Uploaded the NEW book into my e-reader, followed by just one of the earlier books (Selected "ereader" - ie: NOT all items, or borrowed items, or.... Opened the books in the ereader area to confirm that they opened there). 17. Disconnected e-reader from computer. Success at last! 18. Re-connected e-reader to the computer. 19. Re-uploaded the rest of what were the problem books to the e-reader. 20. Disconnected e-reader from the computer. I am able to read all my library books again! Of all those steps, I might not have had to do the second half of step 9. But I don't care. I can finally read my library books again.   Perhaps this will resolve other peoples' difficulties with Kobo giving out erroneous and difficult to solve messages about  authorization for library books. ... View more

The so-called "correct answer" is not at all helpful and does not resolve the problem even remotely. I recently got the same error "No record for this loan is found on this machine, it may have been returned". I too was able to "read in browser". The only way to fix the error was to go to the library website and return the copy that supposedly had no record of loan. I then borrowed the book again (mercifully, I did not have to put it on hold and wait for weeks until it was available again). The download was finally completely successful. ... View more

I'm not positive that this is the same problem, but it is one that I have had on numerous occasions with trying to upload library books to my KoboGlo - books that WILL open in Adobe Digital Editions on my computer desktop.... In July 2017, after several agonized times visting the ADE forum, I finally discovered a viable reply from Maureen, who outlined how to fix the problem: Re: Not able to open library books on my Kobo Glo: "Oops! This document couldn't be opened" ​With the following list, I am paraphrasing Maureen's excellent advice that finally released me from my anguish: Delete the problem book(s) from your ereader. Open Adobe Digital Editions on the computer. Check to see if you can read the problem book(s) in ADE. Connect your e-reader. Erase authorization on ADE (Go to the Help Menu at the top). Erase the authorization for the ereader (go to the side menu of ADE). Keep the e-reader connected to the computer. Go to your public library website and get a NEW book. Upload the new book to ADE. Adobe will then PROMPT YOU for the authorization. If it doesn't, go back to "help" at the top and reauthorize ADE. Go to the side menu of ADE to re-authorize your ereader. Drag the new book into your e-reader. Select "ereader" (ie: NOT all items, or borrowed items, or...). Try opening the book in the ereader area. If it opens there, it's likely that it will open in your e-reader. Re-upload what were the problem book(s) to your e-reader. Again, select "ereader" in ADE and check that the book(s) can be read there. Disconnect your e-reader from the computer. Be able to read your book(s) at last! ______________________________ If the above doesn't work, try the following that DID work for me in July 2018 when the first fix stopped working, largely because ADE kept crashing. (I had to uninstall and reinstall ADE from my computer 5 or 6 times before everything finally worked again....) Once it was FINALLY working, I still had to follow the extra steps outlined above to make sure the book really really really was authorized. Uninstall Adobe Digital Editions: Start > Settings > Control Panel > Add Remove Programs Copy folder C:\my documents\my digital editions and save it elsewhere Delete "C: \my documents\my digital editions” Re-install Adobe Digital Editions Reauthorize ADE and continue as per normal. Be prepared to have to follow the extra steps outlined above. If uploading a large new ebook to Kobo, when ADE stops responding, ignore the message, unplug Kobo from the computer and be pleased to see that the book is uploaded to Kobo after all. Source: (from https://forums.adobe.com/thread/698321 ) Hope that helps! ... View more

I have had similar problems in the past; I finally discovered a viable reply from Maureen, who outlined how to fix the problem:  Re: Not able to open library books on my Kobo Glo: "Oops! This document couldn't be opened" (https://forums.adobe.com/message/8628518#8628518) With the following list, I am paraphrasing Maureen's excellent advice that finally released me from my anguish: 1. Delete the problem book(s) from your ereader. 2.Open Adobe Digital Editions on the computer. Check to see if you can read the problem book(s) in ADE. Connect your e-reader.  Erase authorization on ADE (Go to the Help Menu at the top). Erase the authorization for the ereader (go to the side menu of ADE). Keep the e-reader connected to the computer.     3. Go to your public library website and get a NEW book. Upload the new book to ADE. Adobe will then PROMPT YOU for the authorization. If it doesn't, go back to "help" at the top and reauthorize ADE. Remember to go to the side menu of ADE to re-authorize your ereader.     4. Drag the new book into your e-reader. Select "ereader" (ie: NOT all items, or borrowed items, or...). Try opening the book in the ereader area. If it opens there, it's likely that it will open in your e-reader.     5. Re-upload the problem book(s) to your e-reader. Again, select "ereader" in ADE and check that the book(s) can be read there.     6. Disconnect your e-reader from the computer. Be able to read your book(s) at last! ... View more

After several agonized times updating, sync'ing, rebooting, logging-off, logging-on, deleting, re-uploading Digital Reads and/or Kobo and/or books several times, as well as visiting this forum as well as the Kobo forum, I finally discovered a viable reply from Maureen, who outlined how to fix the problem of library books suddenly being inexplicably unauthorized: Re: Not able to open library books on my Kobo Glo: "Oops! This document couldn't be opened" With the following list, I am paraphrasing Maureen's excellent advice that finally released me from my anguish: Delete the problem book(s) from your ereader. Open Adobe Digital Editions on the computer. Check to see if you can read the problem book(s) in ADE. Connect your e-reader. Erase authorization on ADE (Go to the Help Menu at the top). Erase the authorization for the ereader (go to the side menu of ADE). Keep the e-reader connected to the computer. Go to your public library website and get a NEW book. Upload the new book to ADE. Adobe will then PROMPT YOU for the authorization. If it doesn't, go back to "help" at the top and reauthorize ADE. Go to the side menu of ADE to re-authorize your ereader. Drag the new book into your e-reader. Select "ereader" (ie: NOT all items, or borrowed items, or...). Try opening the book in the ereader area. If it opens there, it's likely that it will open in your e-reader. Re-upload what were the problem book(s) to your e-reader. Again, select "ereader" in ADE and check that the book(s) can be read there. Disconnect your e-reader from the computer. Be able to read your book(s) at last! Please note that this really works. You can freely update your devices to their latest versions. The only really hard part about it is choosing another library book. Not exactly hard.... ... View more

Please note that you don't have to downgrade to get kobo to work again. Maureen outlined how to fix it here: Re: Not able to open library books on my Kobo Glo: "Oops! This document couldn't be opened" With the following list, I am paraphrasing Maureen's excellent advice that finally released me from my anguish: Delete the problem book(s) from your ereader. Open Adobe Digital Editions on the computer. Check to see if you can read the problem book(s) in ADE. Connect your e-reader.  Erase authorization on ADE (Go to the Help Menu at the top). Erase the authorization for the ereader (go to the side menu of ADE). Keep the e-reader connected to the computer. Go to your public library website and get a NEW book. Upload the new book to ADE. Adobe will then PROMPT YOU for the authorization. If it doesn't, go back to "help" at the top and reauthorize ADE. Go to the side menu of ADE to re-authorize your ereader. Drag the new book into your e-reader. Select "ereader" (ie: NOT all items, or borrowed items, or...). Try opening the book in the ereader area. If it opens there, it's likely that it will open in your e-reader. Re-upload what were the problem book(s) to your e-reader. Again, select "ereader" in ADE and check that the book(s) can be read there. Disconnect your e-reader from the computer. Be able to read your book(s) at last! ... View more

Please excuse me for replying to myself. The solution that finally worked for me is outlined by Maureen here: Re: Not able to open library books on my Kobo Glo: "Oops! This document couldn't be opened" ... View more

Excuse me for replying to myself... the solution that finally worked for me is this one outlined by Maureen (last year! how unbelievable that this has been going on for so long) Re: Not able to open library books on my Kobo Glo: "Oops! This document couldn't be opened" ... View more

Many thanks for this. While it's a bit convoluted, it does work. And it's very nice that there is no need, after all, to downgrade to ADE3.0 ... View more

Since talking to Theodore at Support, there was a brief and tiny window when I was successful at uploading books to my Koboglo HD. Alas, the window is closed again. A book that I have borrowed and CAN read on the computer (hardly ideal) is going to expire in 6 days. I was on hold for this book for several days. Perhaps it's a sign from ADE that I shouldn't read the book. But shouldn't that be MY decision, not ADE's? As far as I can tell, there has been no update from ADE to resolve this issue. I'm quite reluctant to revert back to 3.0 because I still have one library book that I am able to read. ... View more

After perusing this forum for other possible fixes, and reading the replies to javastop's question in March of this year, on this very subject (https://forums.adobe.com/thread/1499879), I called the 800 number provided by jackieg: "you might want to give Kobo a call...Please give us a call at 1 (800) 368-5390 from 9 AM to 9 PM, 7 days a week" I spent quite a long time with Theodore, who was very willing to assist. He walked me through the very steps that I have gone through several times on my own (removing Kobo authorization, removing ADE authorization, re-authorizing ADE, re-authorizing Kobo, ascertaining that the library books were indeed in the Kobo and that the annoying message was still present for each book). He then put me on hold for about 3 minutes, only to return to tell me the bad news: This is a known issue (duh...) and that there will be an update within 48 hours. Fingers crossed that the update will fix the nightmare. I really don't want to have to go back to hardcover library books. They're not nearly as easy to read at night.... ... View more

I too am having the same problem since updating KoboGlo and ADE to the latest versions. I've updated, sync'ed, rebooted, logged-off, logged-on, deleted, re-uploaded Digital Reads and/or Kobo several times. I have removed the library books and re-uploaded them. I also did a factory reset on the Kobo (therefore removing all of my books) But still, after each time, I get the message "Your eReader is not authorized to open this book [and] is protected by Adobe Digital Rights Management (DRM). Because you previously deauthorized your eReader, you need to re-import the book using Adobe Digital Editions (ADE)".  Before doing the factory reset, the only thing that changed was that suddenly, a library book that I was able to read began to display the "not authorized" message. Note that I am able to read the books on my computer. They are just not showing in Kobo. Please provide a real solution to this, rather than claiming that "What happens?" is the correct answer. ... View more