Fix PDF Text Changed to Square Symbols Due to Font Issues
Question details
The user needs to resolve an issue where lines of text in a PDF document are displaying as unreadable square symbols instead of standard characters.
- Product
- PDF Reader
- Device & OS
- not provided
- Scenario
- Opening, reading, or editing a PDF document where specific fonts fail to render correctly.
- Observed behavior
- Several lines of text throughout a PDF suddenly display as square symbols. This is likely due to missing local fonts, incorrect font embedding, or a damaged font substitution process.
Verify if you have the original font files installed on your system. If the document uses a custom or licensed font, installing it locally can instantly resolve rendering issues.
Enable the Use Local Fonts Option in Acrobat
Rendering issues often occur when local system fonts are ignored by the PDF reader. Enabling this setting allows the software to pull missing fonts from your device.
If a PDF was saved without proper font embedding, the PDF reader might substitute the text with square symbols. Forcing the reader to use local system fonts can instantly restore readability.
On Windows, open your PDF and navigate to Edit > Preferences. On macOS, click Adobe Acrobat > Preferences from the top menu bar.
From the Categories menu on the left side of the Preferences window, select 'Page Display'.
Locate the 'Rendering' section on the right pane. Check the box labeled 'Use Local Fonts' and click OK to apply the changes.
Close the software completely, relaunch it, and open your PDF document again to see if the square symbols have reverted to standard text.
Analyze and Fix Font Errors using Preflight
If enabling local fonts does not work, the PDF itself might have corrupted font embeddings. The Preflight tool can identify and potentially fix these structural issues.
Read and Edit PDFs Smoothly with WPS Office
If you are struggling with complex font embedding settings in other software, WPS Office provides a lightweight, highly compatible PDF reader and editor that automatically handles font substitutions to ensure your text displays correctly.
- 1. Download and Install: Download WPS Office from the official website and install the application on your computer.
- 2. Open the PDF: Launch WPS Office, click 'Open', and select your PDF file that currently displays square symbols.
- 3. View Document: WPS PDF will automatically process the file and attempt to map and display the text correctly using available system fonts.
- 4. Edit Problematic Text: If formatting issues remain, switch to the 'Edit' tab to select the affected text and replace the problematic font with a standard one.
Frequently Asked Questions
Why does my PDF text turn into square boxes?
This typically occurs when the original fonts used to create the document were not properly embedded into the PDF file, or your local device lacks the required fonts and fails to substitute them with valid alternatives.
How can I ensure fonts are embedded when saving a PDF?
When exporting or printing to PDF from word processors or authoring tools, access the export settings or advanced preferences and ensure the 'Embed fonts in the file' option is checked.
Will installing a missing font on my computer fix the square symbols?
Yes. If you know the exact font used in the original document, installing that specific font on your operating system and reopening the PDF will usually allow the text to render correctly.
