epub file is NOT being created

Hi, I'm using Overdrive to "sign out" books from my local library in Toronto.   ADE has been working fine up until recently.   Overdrive still allows me to sign out books.  When I click on "download EPUB", I am taken to ADE, and nothing happens.   ADE is authorized.    I tried erasing the software, and downloading again from Adobe, but nothing changes.   I would appreciate any thoughts.   I'd much rather read on my KOBO than on a PC!

Thanks.