I have come across a weird problem with my Sony PRS-350. All the books I have read have been fine but the latest one has a format problem where at one point it throws a page when the page is only half full.

It is an epub generated by Calibre, as are all my other books. When I look at the epub through Calibre it is fine and there are no strange characters inserted which might cause this to happen. I have a second PRS-350 and the same happens on that one so I don't think the reader is faulty.

I have even used the old Sony library to copy the book across just to see if this caused the same error. It did, so it is something within the reader and not Calibre doing this.

I am baffled as to why this should be and just wondered if anyone had come across this. Does anyone have any idea why this might be happening?
This is just a guess, but I wonder if the data is split between two files at that point? There is a maximum file size of roughly 300kB for older versions of the RMSDK, so larger structures are split into chunks smaller than that. If so, maybe you could recombine the data and split it yourself between chapters so that you don't notice the page break.
Thank you for your reply.

The epub file is 674 kb in Calibre and also on the reader. I have looked at the file on the reader and there is only one file. I have had books much larger with no problem. I am completely baffled.
The epub itself can be larger than 300kB, but no html file inside it can be larger than that. Epubs are just zip files, so you can look inside them if you want to see what is in there. If you open a copy of the epub with Calibre's ebook-edit program, you can look at the data files inside and see if one of them ends right at the page where you have a problem on the ereader. If so, then you know it has to do with that. If not, then the problem is elsewhere.
I have changed the type to zip and extracted the html files but the largest one of these is 56k. All the text in the chapter in question is within one of the files so I am stuck.

If anyone else has come across this I would love to know
The version of RMSDK used on the 350 is old. It's not very tolerant of errors. To me is sounds like there is an error or what RMSDK perceives is an error.

Make sure you have the epubcheck plugin installed. Load the ePub into the Calibre editor and using epubcheck, check for errors and any found, fix them. That should solve the problem.
Thank you for your reply.

I have run epubcheck and I get four errors like this:-

Unknown property 'panose-1'. [page_styles.css]
page_styles.css (line: 8 column: 4)

the lines in the css file referred to are the panose line below:-

@font-face {
src: url(fonts/Book-Antiqua.ttf);
font-family: "Book Antiqua";
panose-1: 2 4 6 2 5 3 5 3 3 4
}

Sadly, I don't know anything about css language, however, I have now run this on all my epub books that I have read over the years and they all show this error but display correctly so I don't think this is causing the error in this particular book.

I am still baffled.
In the editor, look at the chapter that does not fully display. Please post two paragraphs before the disappearing text and two after so we can maybe see what's going on. But you do have to post the chapters with the HTML code.

Aso, click the icon in the toolbar that looks like a bug. That's the built-in error checker. See what you get there.
Put - at panose
Then epub checks will ignore it, but anything that needs it will still work.

That's not the issue!
Thank you for your reply. I think this is what you were asking for:-

Last few paragraphs of chapter
------------------------------
<p class="calibre4">Prospero took no interest in courtesy. He simply turned, opened the door, and left the room, leaving all the farewells to his companion. Caliban had to hurry just to keep up with him.</p>
<p class="calibre4">Fredda watched them go, and found herself once again wondering about Prospero. She did not understand what went on behind those glowing eyes. There was something not quite right about a robot that—that secretive. She shook her head as she crossed the room. Not much point in worrying about it now. She sealed the door shut behind them and scrambled the keypad. Only she and Caliban and Prospero knew the door's keypad combination.</p>
</div>
<div class="s1">
<p class="calibre4">And there were times she thought seriously about taking at least one name off that list.</p>
</div>
</div>
<div class="calibre1">
<div class="s"><div class="calibre3" id="calibre_pb_3"></div>
</div>
</div>
</div>
</body></html>

First few paragraphs of next chapter
------------------------------------
<?xml version='1.0' encoding='utf-8'?>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta name="generator" content="http://calibre-ebook.com"/>
<title>Utopia</title>
<meta name="author" content="Roger MacBride Allen"/>
<meta name="creation-time" content="2019-2-23"/>
<meta name="revision-time" content="2022-9-6"/>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8"/>
<link href="stylesheet.css" rel="stylesheet" type="text/css"/>
<link href="page_styles.css" rel="stylesheet" type="text/css"/>
</head>
<body class="calibre">
<div class="calibre1">
<div class="calibre1">
<div class="s">
<h1 id="calibre_toc_4" class="calibre2">Chapter 2</h1></div>
<div class="s1">
<p class="calibre4">Caliban followed Prospero down the tunnel. It ran for about a hundred meters, and deposited them at the base of a ravine that was otherwise quite inaccessible to the house. Their aircar was hidden there.</p>
<p class="calibre4">"I would like to know what all that was about," Caliban said as they emerged from the tunnel into the cool of the evening.</p>

-------------------------------
The last paragraph in the first chapter beginning 'And there were times' should just be on a new line and not a new screen. I notice there is a class=S1 line before it but don't understand html so not sure what it is. However, I have removed that line in the editor and the one above it and tried again but this still shows on a new screen. Also, I edited the panose line as suggested but it made no difference to the display.