Would you mind share your form with me and send me a screen shot when the error message is up?
You can share your form by doing the following:
1. Click on “Design tab” on the top left corner.
2. Click on the “Share” icon on the bottom left corner.
3. Click on “Add Collaborator” on the popup menu.
4. Enter email@example.com under “People to share with”.
5. In the Message edit box, type in the title of this issue
6. Click the “Share” button on the bottom right of the dialog.
Thanks for your reply, i have been experimenting and it turns out the error occurs when i change the filename without keeping .pdf in the filename.
So that’s really what happens, if i change the name of the file from e.g response.pdf to just response the file is not recognized by the computer as a .pdf file.
I am glad that you found the problem.
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