Setting License Key in Web.config

This problem has been solved since IronOCR version 2024.3.4.

Exception: Unhandled exception. IronSoftware.Exceptions.LicensingException: IronOCR must be licensed for development.

For older IronOcr versions, specifically those between versions 2023.4.13 and 2024.3.4, there is a known licensing issue in:

  • ASP.NET projects
  • .NET Framework version >= 4.6.2

The key stored in a Web.config file will NOT be picked up and used by the product.

Workaround

To address this issue, it is recommended to retrieve the license key from the Web.config file using ConfigurationManager in the code, and then apply it to the License.LicenseKey property.

Example:

<configuration>
  ...
  <appSettings>
    <add key="IronOcr.LicenseKey" value="IRONOCR-MYLICENSE-KEY-1EF01"/>
  </appSettings>
  ...
</configuration>
<configuration>
  ...
  <appSettings>
    <add key="IronOcr.LicenseKey" value="IRONOCR-MYLICENSE-KEY-1EF01"/>
  </appSettings>
  ...
</configuration>
XML

With the XML file provided above, we can use ConfigurationManager to retrieve the license key value and pass it to the IronOcr.License.LicenseKey property.

using System.Configuration;

// Retrieve the license key from the Web.config's appSettings
string licenseKey = ConfigurationManager.AppSettings["IronOcr.LicenseKey"];

// Apply the license key to IronOcr to avoid licensing exceptions
IronOcr.License.LicenseKey = licenseKey;
using System.Configuration;

// Retrieve the license key from the Web.config's appSettings
string licenseKey = ConfigurationManager.AppSettings["IronOcr.LicenseKey"];

// Apply the license key to IronOcr to avoid licensing exceptions
IronOcr.License.LicenseKey = licenseKey;
Imports System.Configuration

' Retrieve the license key from the Web.config's appSettings
Private licenseKey As String = ConfigurationManager.AppSettings("IronOcr.LicenseKey")

' Apply the license key to IronOcr to avoid licensing exceptions
IronOcr.License.LicenseKey = licenseKey
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Curtis Chau
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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