No supported formats (Available formats: 0) (epub))

[luta]

I've been using Calibre for a while now and never had any problems, just recently though I can convert mobi to epub but whenever I try to convert epub to mobi I get the message No supported formats (Available formats: 0) (epub))

On the right hand side column in Calibre under the book cover/ Title/Authors etc it shows Formats: 0) (EPUB).
'Path when I click to open' shows me Cover/Metadata and the epub file.

When I click to open the epub version in Calibre I just get the 'Open With' option.

Message I get: calibre, version 0.9.28
WARNING: Could not convert some books: Could not convert 1 of 1 books, because no supported source formats were found.

No supported formats (Available formats: 0) (epub))

I'm not in the least technical and wont even pretend to understand how it all works.

I've googled and searched the user manual as well as this forum for info on this but can't find anything that relates!

I'm using the latest version have never changed anything just updated etc.

Any help/info on this would be greatly appreciated.

Thankyou

Edit:
I've managed to find Add Format under the Edit Metadata tab but it just opens My Docs? How do I find where to Add Format from please

[Adoby]

The ePub could be an orphan?

If changes, even very minor, are made to the filenames calibre may loose track of the books. One cause is if the library is used from Linux and Windows, they treat upper/lower case in filenames different. Another cause is if you accidentally have changed the filename.

Copy the ePub and run the library maintenance to check your library.

You may have to manually add back books that calibre has lost track of.

[luta]

Originally Posted by Adoby

The ePub could be an orphan?

If changes, even very minor, are made to the filenames calibre may loose track of the books. One cause is if the library is used from Linux and Windows, they treat upper/lower case in filenames different. Another cause is if you accidentally have changed the filename.

Copy the ePub and run the library maintenance to check your library.

You may have to manually add back books that calibre has lost track of.

Ran the library maintenance, some of the boxes had ticks again so I checked fix. Restarted Calibre and the book will now load, appreciated.