Start with the latest version for security fixes. If you experience instability, downgrade to the previously known stable version (v1.04 for H/W A1).
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Before you begin the download, follow these steps to prevent "bricking" your device: Start with the latest version for security fixes
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Perform a factory reset. Use a paperclip to hold down the Reset button on the back of the router for 10 seconds while it is powered on.