Orphaned Html2Pdf.exe processes after HTML-to-PDF conversion

[alessandro.tl]

Issue Summary:
When converting .html documents to PDF using Spire.Office 10.8.0 with QTPlugin in a .NET Framework 4.8 WCF application, the conversion completes successfully but the Html2Pdf.exe process started during conversion never terminates.

Each subsequent .html conversion spawns a new Html2Pdf.exe process, which remains active, leading to progressive RAM consumption until the server runs out of memory.

Environment:

Product: Spire.Office 10.8.0
Framework: .NET Framework 4.8 (v4.8.04161)
OS: Windows Server 2022 Standard, Version 21H2, OS Build 20348.3932
Architecture: x64
Application Type: WCF Application

Technical Details:

Faulting Application: Html2Pdf.exe
Faulting Module: Qt5WebEngineCore.dll (v5.14.2.0)
Exception Code: 0x80000003
Fault Offset: 0x000000000020620ee
Event Viewer: Application Error (Event 1000) and Windows Error Reporting (Event 1001) attached.

Reference code:

Code: Select all

using (MemoryStream ms = new MemoryStream())
         {
            HtmlConverter.Convert(
               url: <html string>,
               stream: ms,
               enableJavaScript: false,
               timeout: 100000,
               pageSize: PdfPageSize.A4,
               margins: new PdfMargins(0),
               urlHtml: LoadHtmlType.SourceCode);
            return ms.ToArray();
         }

[talia.liu]

Hello,

Thank you for your inquiry.
I will conduct further tests and this process may require some time. May I ask if you have any antivirus software installed on your system? This could also potentially cause the issue.

[talia.liu]

Hello,

Thank you for your patience.
Which QT package did you download and use? Is it the x64 package or the x86 package?
I have simulated an HTML file and conducted tests with the x64 package, but I was unable to reproduce the issue you mentioned. To help us investigate more accurately, could you please provide us with your HTML file or a reproducible sample project? You may upload the files as attachments or send them directly to my email: [email protected]. Thanks in advance.

[alessandro.tl]

Hello,

Thank you for your follow-up. Here are the details you requested:

- We downloaded and installed the Windows x64 package from the official page.
- The plugin is installed inside our WCF service directory under IIS, e.g.:
C:/inetpub/wwwroot/converter.wcf/plugin
- Our antivirus software has been configured with an exclusion for the above path.
- The issue only occurs on the specific machine mentioned in the ticket. When running the same code and configuration on another PC, everything works correctly.
- The issue happens with any .html file, so it is not related to a specific file.

Best regards

[talia.liu]

Hello,

Thank you for providing more detailed information.
In my testing environment, even using IIS in the same scenario did not reproduce this issue. With the assistance of our Dev team colleagues in analysis, we suspect that this issue may be related to dependencies of the Qt plugin. Please test again in your environment using the new version of the Qt plugin via the link below. We look forward to your test results.
Link: https://www.e-iceblue.com/downloads/plugins/qt-6.5.3-plugins-windows-x64.zip

[alessandro.tl]

Hello,

Thank you for your prompt response and for providing the updated plugin.

We have updated the Qt plugin using the new version from the link you provided, but unfortunately the issue still persists.

We have also double-checked our antivirus configuration to ensure that the path containing the plugin is excluded, but the problem remains.

Please let me know if there are any additional steps or dependencies we should verify to further troubleshoot this issue.

Best ragards,
Alessandro

[talia.liu]

Hello,

Thank you for your feedback.
To further analyze possible reasons in your environment, please run the following command in your environment's plugin directory.

Code: Select all

echo "<p>test text</p>" | Html2Pdf.exe "placeholder" "d:\output.pdf" 800 600 0 0 0 0 1

test.png

Then you can check if the issue still persists. If so, this should be related to your specific environment, as Qt plugin is a third-party plugin that has some dependencies on the environment. Sorry we currently do not have a good way to modify its underlying logic.
Additionally, for converting HTML to PDF using Spire.PDF, you might consider an alternative conversion method—using ChromeHtmlConverter. For specific usage instructions, please refer to the following tutorial:
https://www.e-iceblue.com/Tutorials/NET/Spire.PDF-for-.NET/Program-Guide/Conversion/C-Convert-HTML-to-PDF-using-ChromeHtmlConverter.html
We look forward to your feedback.

[alessandro.tl]

Hello,

Thank you for your support and the suggestions provided.

We have addressed the issue on our side by modifying our software to use Spire.Doc for converting HTML files, which resolved the problem.

Best regards,
Alessandro

[talia.liu]

Hello,

Glad to hear your issue has been resolved.
If you have any questions or need further assistance, please don't hesitate to let us know.