Problems with PDF attachments in Outlook 2016/2019

Question

Hi all,
i have trouble when i attach signed PDF file to email.
If i:

1. Open outlook
2. Open new email
3. Add recipient (me)
4. Attach a SIGNED pdf file
5. Send
6. Receive this email (no matter in wich program i will open it - Outlook or Thunderbird)

PDF reader (no matter wich one) says:
(translated by Bing):
Error verifying signature. Unexpected byte range values define where the signed data is. Details: Signature byte range is invalid

One work around what i was find is: Compress it to ZIP - in this case everthing is right.
No matter wich account i will use (from my organization or from @Stuff .com)

If i will send it by Thunderbird everything is fine and signatures are correct.

So it seems Outlook doing something wrong with PDF file or signature itself.

Product: Outlook 2019, MAPS version: Version 2103 (compliation: 13901.20462, Fast installation)
Microsoft Office Professional Plus 2019

some addtional data are in Polish in links bellow, but i was send here cause its MAPS.

Links:
https://answers.microsoft.com/pl-pl/msoffice/forum/msoffice_outlook-mso_win10-mso_2016/problem-z-outlook-20162019-za%c5%82%c4%85czniki/52a8b24b-e6af-439f-bee8-2d690b9f0035?tm=1619508680091
https://www.outlook.pl/forum/viewtopic.php?f=8&t=9658

I hope something can be done case compress to ZIP every signed PDF file make me crazy.

Thanks for any response.
Zibi

Answer 1

Hi @Zbigniew Szlachta ,

Welcome!

Before going further, please kindly forgive us not know much about "signed PDF files" here. Do you mean that by signing the PDF file via "Fill & Sign" option? Or something else?

And does this preview issue only happen to signed PDF files? Can you preview other unsigned PDF files normally?

In order to further confirm if the issue is related to your Outlook desktop client, I would suggest you to log in to your web mail and preview the same "signed PDF files" there to see if the issue has any difference. For example, you could click the "preview" button on Outlook.com web mail to preview your PDF files like below:

I tried to sign the PDF file via "Fill & Sign" option and added the file I got as attachment to Outlook 2019, everything seems just work fine. I can preview the PDF file normally and cannot reproduce your issue.

Any update, please feel free to post back.

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Answer 2

Ok,
In my software, I electronically sign a pdf document using a qualified signature.
next i try send it:

after receive this email i have empty preview of 1st page (in oryginal document everything is good):

when i open it with Acrobat Reader DC i still have blank 1 page and additonally Acrobat says now there is problem with signature:

When i will double click on signature to verify it Acrobat show:
Error verifying signature. Unexpected byte range values define where the signed data is. Details: Signature byte range is invalid

I dont care about Preview, but more important is verification of signature, what is in this case incorrect.
And additionally document PDF is damaged (1st page is blank)
As i describe above in Thunderbird after this same action everything is fine
Only one option for Outlook is compress PDF to ZIP (in this case signatures after send are veryfied OK).