I made a previous thread (
here) about this issue. I have since narrowed down the problem to a change in Calibre that happened sometime between version 0.7.35 and version 0.7.45. I suspect that the change happened around the new year in the flurry of updates that happened and I was going back one version at a time, but it was very onerous, so I found a file that I knew worked, created with an older version, and went back to that version (which happened to be 0.7.35). All updates from the current version 0.7.56 through 0.7.45 exhibit the same glitch.
Using the Kindle, you can highlight text of a document and are given the choice to add a message/note and then share your message and the text online. It uploads to your Facebook, Twitter, and/or your user profile at
https://kindle.amazon.com/.
Once you have highlighted text, it looks like this:
When you press alt+enter, and it is successfully shared, you see this message:
In files created by newer versions of Calibre, however, you see this error:
If there is any way to narrow down what change happened in Calibre affecting the conversion of documents to the MOBI format for use on Kindle between the old and new versions, I'd really appreciate it! In the meantime, I have downgraded to an older version, but if there's any way to get a fix I'd appreciate it!