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Hi,

I use the PDF Filler action of PDF.co to fill a PDF file with WPForms entries.

Image fields are optional so the checkbox “Allow Empty Text and Image Objects” is checked.

It was working great until 08/03/2025.

I have not edited my zap but today, 5 days later, all empty optional image fields have the following error: “Parameter "url" (position 4) must be a non-empty string”.

Same error when the checkbox is unchecked.

I try to regenerate the previous succeeded PDF, same error.

I need help !

Thanks

 

Hi ​@tipikae 

Try these options:

Hey there, ​@tipikae 👋

Just stumbled across this and saw you reached out to our Support team and it seems PDF.co were able to implement a fix on their end. 🎉

Out of curiosity, was the fix they made to “their module” specific to your PDF.co account, or to the PDF.co app in general? Just wondering whether folks would need to reach out to PDF.co directly to get a similar fix in place if they run into the same issue.

Looking forward to hearing from you! 

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