Fix Acrobat Compare Files Not Working When Comparing Tagged PDFs
Question details
The user is unable to compare two tagged PDF files because the Compare Files feature fails to respond.
- Product
- Adobe Acrobat Pro DC
- Device & OS
- not provided
- Scenario
- Comparing the differences between two tagged PDF documents.
- Observed behavior
- The Compare Files feature does nothing when initiated, even though both files pass accessibility checks and the Compare Text Only option is available.
Ensure both tagged PDF files are saved locally on your computer rather than on a network drive, and verify that your Adobe Acrobat Pro DC is updated to the latest build.
Adjust File Settings and Comparison Mode
Simplify the environment and document parameters to bypass structural conflicts causing the tool to freeze.
Tagged PDFs contain hidden structural metadata for accessibility. Sometimes, a complex or specific tag structure can cause the comparison engine to hang.
Save copies of both PDF files using simple, short alphanumeric filenames without any special characters or spaces.
Temporarily disable security restrictions by navigating to Edit > Preferences > Security (Enhanced) and turning off Protected View.
Open the Compare Files tool, click the Settings (gear) icon, and manually select a different comparison mode, such as 'Compare Text Only', to see if the engine responds.
Reset Acrobat Preferences and Repair Installation
Clear corrupted software configurations that might be preventing the compare tool from launching correctly.
Use WPS Office to Compare PDFs Without Hassle
If Acrobat's compare feature remains unresponsive, you can quickly spot differences between your documents using the reliable PDF tools built into WPS Office.
- 1. Open WPS Office: Launch WPS Office and navigate to the PDF tab on the main home screen.
- 2. Access the Compare Tool: Go to the Tools or View tab and click on the 'Compare' or 'Side-by-Side View' feature.
- 3. Upload your files: Select your original PDF file and the modified PDF file from your local storage.
- 4. Start comparison: Click the Compare button to instantly review the highlighted differences without software unresponsiveness.
Frequently Asked Questions
What are tagged PDFs and why do they cause comparison issues?
Tagged PDFs contain hidden structural metadata, such as reading order and element tags, designed for screen readers. Overly complex or corrupted tags can occasionally cause comparison engines to freeze while trying to parse the document's underlying structure.
Can I remove tags from a PDF to make it compare successfully?
Yes. You can effectively strip tags by printing the document using the 'Microsoft Print to PDF' printer. This creates a flat PDF that often bypasses structural comparison errors.
Why is the Compare Text Only option grayed out or unresponsive?
This usually happens if the PDF is generated from scanned images without a recognized text layer. You must run Optical Character Recognition (OCR) on the document first to convert the images into readable text before comparing.
