ACCESSIBLE PDFs: How to Correct “F” or “UF” Key Missing in File Specification Error

Four Adobe PDF Icons in a row

Using InDesign to export a PDF file?

Sometimes you will find the error “‘F’ or ‘UF’ key missing in file specification” when checking the accessibility of the PDF in PAC 3.

PAC 3 Error F or UF

Here’s how to fix it, using Adobe Acrobat Pro:

1) Open the PDF in Adobe Acrobat Pro DC.

2) Select More Tools > Print Production >Preflight.

3) Select the Acrobat Pro DC 2015 Profiles from the drop-down within the Preflight dialog box.

How to correct F or UF key using Preflight Tool in Adobe Acrobat Pro

4) Click the blue wrench icon.

5) Under the Document category, select the Insert missing F and UF entries for embedded files option.

6) Press the Fix button in the bottom right corner of the dialog.

7) Save the PDF file.

8) Test the PDF again in PAC 3.

PAC 3 F or UF Key Error Corrected

9) The original error should now “pass” as accessible.


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