Resolving MissingMethodException and AWS SDK Compatibility in .NET Applications

When using an iText Remote Reporting Volume License in a .NET application, a runtime exception may occur that is only visible when logging is enabled:

TEXT

System.MissingMethodException: Method not found: 'System.DateTime Amazon.CognitoIdentity.Model.Credentials.get_Expiration()'.

This appears during License validation, or when the application attempts to connect to iText servers.

Cause

The iText licensing remote library currently depends on AWSSDK.CognitoIdentity 3.x. If your application explicitly references AWS SDK 4.x, NuGet may resolve incompatible AWS assemblies as AWS SDK 4.x contains breaking changes in the API.

This results in the MissingMethodException as outlined above.

Resolution

✅ Option 1 : Align AWS SDK Versions

To avoid this issue, explicitly reference the AWS SDK 3.7.x packages in your project file:

XML

    <PackageReference Include="AWSSDK.CognitoIdentity" Version="3.7.502.40" />
    <PackageReference Include="AWSSDK.Core" Version="3.7.500.75" />
    <PackageReference Include="AWSSDK.Kinesis" Version="3.7.505.34" />
    <PackageReference Include="AWSSDK.SecurityToken" Version="3.7.504.29" />

Any recent 3.7.x version is supported.

✅ Option 2: Remove AWS SDK References

If your project does not require the AWS SDK directly, you can simply remove all explicit AWS SDK.* package references and allow iText to resolve the compatible versions automatically.

Additional Notes

AWS SDK 4.x is not currently supported and will throw an exception as mentioned above.
The issue is unrelated to license connectivity to iText servers