For weeks now I've been having a problem adding additional formats to existing books (as opposed to adding new books, which works fine). For e.g. adding a format to an empty book, or adding another format to a book that already has one. When I try it, nothing happens; I just get a busy cursor until I eventually have to shut down Calibre via the Task Manager.
This particular task worked perfectly fine in the past; I'm not sure what I'm doing wrong now
Some info: I'm presently up to Calibre version 0.9.29 (32-bit); Win 7 64-bit system, as of today running 16GB of RAM (previously 4GB).
Any thoughts?