> For the complete documentation index, see [llms.txt](https://docs.ndi.video/all/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.ndi.video/all/faq/common-issues/im-having-issues-installing-version-x-of-unreal-engine.md). # I'm having issues installing version (X) of Unreal Engine If you're experiencing issues installing a particular version of Unreal Engine it may be because the NDI Unreal Engine SDK requires that Unreal be installed prior to installation. The installer checks for registry keys in this install location `HKEY_LOCAL_MACHINE\SOFTWARE\EpicGames\Unreal Engine\InstalledDirectory.` If the registry keys are not there, then the installer will be unavailable and appear grayed out for that particular version. --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation by asking a question. Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters: ``` GET https://docs.ndi.video/all/faq/common-issues/im-having-issues-installing-version-x-of-unreal-engine.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is what the user is ultimately trying to achieve, the reason they need the answer. Sharing it helps GitBook give you a better, more relevant answer. A goal is most helpful when it describes the outcome the user wants rather than restating the question. For example, with `ask=how do I create an API token`, a goal like `automate deployments from our CI pipeline` lets GitBook tailor the answer to that use case. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.