Oje, 5 years ago we had a problem with missing metadata on pocketbook devices.
See this german thread:
www.mobileread.com/forums/showthread.php?t=224126
Maybe it's still not solved completely? I finally switched to kobo and tolino, so I'm not up-to-date with pocketbook problems.
However, I've found that my pocketbook reader wanted metadata like that in the opf:
Code:
<metadata xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:opf="http://www.idpf.org/2007/opf">
<dc:creator opf:role="aut" opf:file-as="Christie, Agatha">Christie, Agatha</dc:creator>
<dc:title>Das fehlende Glied in der Kette</dc:title>
<dc:subject>Krimi</dc:subject>
<dc:language>de</dc:language>
<dc:publisher>Fischer</dc:publisher>
<dc:date>1920-01-03</dc:date>
<dc:description>Der Fall scheint klar, alle Hinweise deuten auf den Ehemann des Opfers als Täter. Der jedoch kann das tödliche Gift nicht zur angegebenen Stunde erworben haben. Hercule Poirot und sein Freund Hastings geben nicht auf, bis das fehlende Glied in der Beweiskette gefunden ist … Der erste Roman von Agatha Christie und zugleich Hercule Poirots Debüt!</dc:description>
<dc:identifier id="BookID">9783104021294</dc:identifier>
<dc:identifier opf:scheme="mobi-asin">B00XLC19K4</dc:identifier>
<dc:identifier opf:scheme="isbn">9783104021294</dc:identifier>
<meta name="calibre:series" content="Hercule Poirot"/>
<meta name="calibre:series_index" content="1.0"/>
<meta name="cover" content="cover"/>
</metadata>
(Series infos last; series_index after series)
The pocketbook reader didn't read metadata info under the line with series_index. And it didn't like the metadata lines switched (it wants meta name="" first, followed by content="")
I sorted the metadata for my pocketbook reader by hand (calibre editor) and transfered the books with windows explorer to my eBook reader. (Calibre is updating the metadata during file transfer and mixing the metadata-lines again.)