If I've tried all the common solutions and still encounter Error 1004, what are my remaining options?

If all else fails, consider seeking help from experienced Xiaomi community forums or contacting Xiaomi support directly. They may have device-specific solutions or be aware of ongoing server-side issues. As a last resort, and only if you're comfortable with advanced procedures, you might explore alternative unlocking methods, but these carry a higher risk of bricking your device.