> For the complete documentation index, see [llms.txt](https://cesium.gitbook.io/cesium-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://cesium.gitbook.io/cesium-docs/support/antivirus-flagged-launcher.md). # Windows Defender or my antivirus flagged the launcher The launcher loads code into a running game, which is what antivirus software is built to notice. {% hint style="info" %} The launcher loads code into a running game, which is what antivirus software is built to notice. {% endhint %} ## Why it happens The Cesium Launcher attaches to a running Minecraft process and loads the client into it. That is the same mechanism some malware uses, so antivirus heuristics flag it. It is a false positive. ## What to check * You downloaded the launcher from your Cesium dashboard, not from a link someone sent you. ## Let it run Windows Defender: open Windows Security, Virus and threat protection, Protection history. Find the launcher entry and choose Allow on device. Then add the launcher's folder as an exclusion under Manage settings, Exclusions. Other antivirus: add the launcher's folder to the exclusion or allow list. The exact steps depend on the product. ## Still blocked Some antivirus products remove the file before you can allow it. Add the exclusion first, then download again. --- # 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://cesium.gitbook.io/cesium-docs/support/antivirus-flagged-launcher.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.