Final answer:
Ian should update the application to resolve the issue of it being unsupported, as developers often issue updates for software to remain compatible with newer technologies.
Step-by-step explanation:
When Ian encountered an error stating that the version of the software application was no longer supported, the most straightforward solution is to update the application. This is because software developers routinely release updates to fix bugs, enhance security, and add new features. An update often includes support for newer operating systems or patches for issues that render older versions obsolete.
Reinstalling the operating system, changing computer settings, or using a different device may not address the specific issue of the application being outdated. Therefore, the best course of action for Ian is to look for an update to the application, which can usually be done within the application itself or by visiting the developer's website.