How to Fix Invalid Font Object Error When Saving a PDF in Acrobat
Question details
The user is unable to save a PDF or merge scanned documents due to an error message stating there is an invalid font object or font descriptor object.
- Product
- Adobe Acrobat
- Device & OS
- Windows 10
- Scenario
- Saving a PDF that contains specific character sets like Cyrillic/Russian, or attempting to merge multiple scanned PDF documents.
- Observed behavior
- Acrobat fails to save or merge the document and prompts the error message 'Invalid font object or font descriptor object'.
Ensure you have a backup copy of your original PDF files and verify if there are any pending updates available for your current version of Adobe Acrobat.
Rebuild Scanned PDFs Using OCR or Recreate from Source
Recreating the PDF from the original source file or running OCR on scanned documents often resolves embedded font corruption.
Corrupted or malformed font descriptors usually occur when text layers generated by older OCR engines conflict, or when original documents fail to embed fonts properly.
If you have the original source document (such as a Word file), re-export it to PDF, ensuring that the option to embed all fonts is checked.
For scanned PDFs without a source file, open the document in Acrobat and navigate to the 'Enhance Scans' tool in the right pane.
Select 'Recognize Text' to run OCR on the document, which will rebuild the text layer and associated font descriptors.
Attempt to merge the newly processed documents or save the file again to confirm the error is resolved.
Flatten the PDF via Print to PDF
Printing the problematic PDF to a new PDF file can flatten malformed font objects and strip out the errors.
Update Adobe Acrobat
Older versions like Acrobat XI or Acrobat 2017 may have known bugs handling specific font descriptors that are patched in later releases.
Merge and Save PDFs Without Font Errors Using WPS Office
WPS Office includes a highly capable, lightweight PDF editor that smoothly handles document merging, OCR, and font embedding. Skip legacy font object errors by using WPS PDF to manage and combine your files effortlessly.
- 1. Launch WPS PDF: Open WPS Office and click on the 'PDF' tab to access the built-in PDF tools.
- 2. Select Merge PDF: Choose the 'Merge PDF' option from the main dashboard or the toolkit menu.
- 3. Add your files: Click to upload the scanned PDF documents you want to combine and arrange them in the correct sequence.
- 4. Combine and save: Click the 'Merge' button to seamlessly combine the files, then save the new document to your computer without triggering font errors.
Frequently Asked Questions
Why does Acrobat say 'Invalid font object' when saving?
This error typically occurs when a PDF contains corrupted, malformed, or improperly embedded fonts. It is especially common when working with specific character sets like Cyrillic, or when legacy fonts are not supported by the current PDF specifications.
Can I fix the font object error without the original source file?
Yes. If you do not have the original Word or source document, you can often fix the issue by 'refrying' the PDF (printing it using the 'Microsoft Print to PDF' printer) or by running an OCR scan on the document to rebuild the corrupted text layers.
Does the Preflight tool in Acrobat fix font errors?
The Preflight tool in Adobe Acrobat can identify and sometimes repair syntax issues within a PDF file, including broken font descriptor objects. You can run a syntax check and fix profile in Preflight to analyze and repair the embedded fonts before saving.
Why does merging scanned PDFs trigger font errors?
Scanned PDFs often contain hidden text layers generated by various OCR engines. Merging files from different sources can create conflicting or broken font descriptors, causing Acrobat to fail and display an error when saving the newly combined document.
