"Gary" has asked how he can restore system files on his NXT brick if they're inadvertently deleted. Here's how: 1) Open up your NXT-G software and connect your brick to your computer. Make sure that you're connected to the internet. 2) Go up to the "Tools" menu and drag down to "Update Firmware". 3) In the new window that pops up, click "download". 4) After a few seconds, you'll hear a multi-toned sound. That means that all of your original system files are now back on your brick.