AdaptiveRenderEngine Unhandled Case: Fix

Updated:June 1, 2025

{
  "message": "Unhandled case for AdaptivePdfRenderer.DetectActiveRenderingEngine",
  "exceptionType": "System.ArgumentException",
  "exceptionDetail": "Unhandled case for AdaptivePdfRenderer.DetectActiveRenderingEngine",
  "modelState": null,
  "propertyErrorList": null
}

This rare exception typically occurs for users running legacy versions of IronPDF alongside the deprecated IronPdf.EAP package.

Possible Cause

The error usually arises during runtime in projects deployed on specific platforms, particularly in C# Web API projects hosted in a Linux environment. It is likely due to issues with the deployment of runtime files from the IronPdf.EAP package.

Solution

To resolve this issue, please upgrade to the latest version of the IronPdf package and discontinue using the IronPdf.EAP package, as it is deprecated and no longer maintained.

Should you need further support, kindly submit an Engineering Request.

Curtis Chau

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Technical Writer

Curtis Chau holds a Bachelor’s degree in Computer Science (Carleton University) and specializes in front-end development with expertise in Node.js, TypeScript, JavaScript, and React. Passionate about crafting intuitive and aesthetically pleasing user interfaces, Curtis enjoys working with modern frameworks and creating well-structured, visually appealing manuals.

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