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Wed Nov 19, 2025 7:34 am

Hi,

We are having issues when converting a simple Word document to PDF. The Word document contains some digital signatures.
These Word files are not created by us — they come from another system, so we have no control over how they are generated.
Conversion code:
Code: Select all

using (var doc = new Document(request.FileStream, Spire.Doc.FileFormat.Auto))
{
    doc.SaveToStream(response.Stream, Spire.Doc.FileFormat.PDF);
    response.Stream.Position = 0;

    return response;
}


Error we get:
System.FormatException: String '2025-11-18T10:36:30.4Z' was not recognized as a valid DateTime.
at spr该.䘙(spr媕 A_0, DigitalSignature A_1)
at spr该.䘥(spr媕 A_0, DigitalSignature A_1)
at spr该.䘓(Stream A_0, spr䙀 A_1, spr诇 A_2)
at spr该.䘓(Stream A_0, spr䙀 A_1, spr诇 A_2, DigitalSignatureCollection A_3)
at spr锕.䘖()
at spr锕.䘓(Stream A_0, Document A_1, spr輕 A_2)
at Spire.Doc.Document.䙘(Stream A_0)
at Spire.Doc.Document.LoadFromStream(Stream stream, FileFormat fileFormat, String password)

bradjen
 
Posts: 29
Joined: Thu Jul 25, 2019 6:07 am

Wed Nov 19, 2025 10:32 am

Hello

Thanks for your post.
This issue is because the current date format of this signature is not compatible. We are currently optimizing and fixing this part internally.
The tracking number for this issue is SPIREDOC-11680. Once there are any updates, I will let you know. Thanks for your understanding.

Sincerely,
Lisa
E-iceblue support team
User avatar

Lisa.Li
 
Posts: 1533
Joined: Wed Apr 25, 2018 3:20 am

Thu Dec 11, 2025 10:07 am

Hello,

Thanks for your patience.
Glad to inform you that our latest version (Spire.Doc Pack(hot fix) Version:13.12.2) contains the fixes of SPIREDOC-11680. Please test it.

https://www.e-iceblue.com/Download/download-word-for-net-now.html
https://www.nuget.org/packages/Spire.Doc
https://www.nuget.org/packages/Spire.Docfor.NETStandard/13.12.2

Sincerely,
Lisa
E-iceblue support team
User avatar

Lisa.Li
 
Posts: 1533
Joined: Wed Apr 25, 2018 3:20 am

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