[BobC]

Windows 8.1
Calibre 4.19
Kobo Glo 4.21.15015

I have a large library where all the books have been converted to KEPUB using the Kepub Output plug-in and I then upload them to my Kobo Glo WITHOUT using the Extended driver. This has worked fine for years.

Since the update to Calibre 4.19 I noticed that new books I uploaded could not be opened on the Glo which exited with a "Oops! this document couldn't be opened" error. At first I attributed this to a problem in the conversion process, however this is not the case.

I found a book in my library that had been converted some time ago and I had read it on the Glo. I then re-uploaded it using Calibre and found it could not be opened and returned the same error. By doing this I made sure that the problem was not with the conversion process. This suggests that the book is being corrupted in the transfer process.

The book appears to be imported by the Glo into its database when I eject the reader and appears in the listings. It does appear as a <name>.kepub.epub on the Glo and using file tools on my PC I can view the contents of the file by unzipping it and examining the structure.

Any ideas what is going on here ?

BobC