In EPUB files, the clickable Table of Contents (ToC) allows readers to navigate easily. If “(Untitled)” appears in the ToC, it’s usually because a chapter or section in the source document lacks a title, so the software fills in a placeholder.
This issue can happen in both EPUB2 and EPUB3 formats:
- In EPUB2, the ToC structure is typically managed by a toc.ncx file.
- In EPUB3, the ToC is managed by a toc.xhtml or nav.xhtml file in HTML format.
How to solve it?
To resolve this issue, you need to ensure that each chapter or section in your EPUB has a defined title and then update the navigation (ToC) files in Sigil. Here’s a step-by-step guide to achieving this.
Step-by-Step Guide to Fixing the “(Untitled)” Placeholder in Sigil
Step 1: Install and Open Sigil
- If you haven’t already, download and install Sigil.
- Open Sigil and load your EPUB file by selecting File > Open and choosing your EPUB file.
Step 2: Inspect the Table of Contents
- After loading your EPUB, go to View > Table of Contents in Sigil’s menu. This will display the current ToC.
- If you see any entries labeled as “(Untitled),” make a note of these. They are likely missing chapter titles or headings in the content files.
Step 3: Locate the Navigation File
In the Book Browser on the left side of Sigil, you’ll see a list of files that make up your EPUB. Look for the relevant navigation file:
- For EPUB2: The navigation file is toc.ncx. You’ll find this under the “Text” folder in the Book Browser.
- For EPUB3: The navigation file is typically toc.xhtml or nav.xhtml. You’ll find this file under “Text” or “Navigation.”
Step 4: Edit the Navigation File
Editing toc.ncx for EPUB2
- Double-click toc.ncx to open it in Sigil’s editor.
- You’ll see XML code that defines the ToC structure. Here’s a sample structure:
<navMap>
<navPoint id="chapter1" playOrder="1">
<navLabel>
<text>Chapter 1: Introduction</text>
</navLabel>
<content src="chapter1.xhtml" />
</navPoint>
<navPoint id="chapter2" playOrder="2">
<navLabel>
<text>(Untitled)</text> <!-- Problematic placeholder here -->
</navLabel>
<content src="chapter2.xhtml" />
</navPoint>
<navPoint id="chapter3" playOrder="3">
<navLabel>
<text>Chapter 3: Methods</text>
</navLabel>
<content src="chapter3.xhtml" />
</navPoint>
</navMap>
- Locate the <navPoint> tags with “(Untitled)” in the <text> element.
- Replace “(Untitled)” with the appropriate chapter title. For example:
<navLabel>
<text>Chapter 2: Background</text>
</navLabel>
- Repeat this for any other “(Untitled)” entries.
Editing toc.xhtml or nav.xhtml for EPUB3
- Double-click toc.xhtml or nav.xhtml to open it in the editor.
- The ToC will be structured in HTML, typically in a list format. Here’s a sample structure:
<nav epub:type="toc">
<h1>Table of Contents</h1>
<ol>
<li><a href="chapter1.xhtml">Chapter 1: Introduction</a></li>
<li><a href="chapter2.xhtml">(Untitled)</a></li> <!-- Placeholder here -->
<li><a href="chapter3.xhtml">Chapter 3: Methods</a></li>
</ol>
</nav>
Find each <a> tag with “(Untitled)” as its text.
Replace “(Untitled)” with the correct title. For example:
<li><a href="chapter2.xhtml">Chapter 2: Background</a></li>
- Make sure each entry reflects the actual chapter titles in your EPUB.
Step 5: Verify Chapter Titles in Content Files
Sometimes, missing ToC entries are due to missing or improperly formatted headings in the actual content files. To ensure each section has a heading:
- In the Book Browser, locate and open the content files (e.g., chapter1.xhtml, chapter2.xhtml) for each chapter.
- Check that each file has a heading tag, such as <h1> or <h2>. For example:
<h1>Chapter 2: Background</h1>
If a heading is missing, add an appropriate one.
Step 6: Save and Validate the EPUB
- After making all changes, save the file in Sigil by going to File > Save.
- Preview the Table of Contents in Sigil’s Preview pane to confirm that the correct titles appear and that no “(Untitled)” placeholders remain.
- To ensure the EPUB is fully valid, use an EPUB validator like epubcheck. This will alert you to any remaining structural issues in the file.
For a smoother process in Word (DOCX):
-
Make sure each section has a clear title using Word's Heading styles (e.g., Heading 1 for chapter titles).
-
Avoid adding blank headings or placeholder text.