It sounds like your brick needs to be reset.  There are two reset buttons try both.  One is in the battery box.  The second is hidden in one of the holes on the back of the brick shine a flashlight in the holes on the back side of the brick under the side of the USB connector.

What version of the software are you using?  What kind of computer (Mac or PC)?  What version of operating system are you using?

V2.1 is the current version but 2.0 has been pretty stable.  I just upgraded to 2.1 this year but haven't used it yet.

From: Haydee Cooper <[log in to unmask]>
Reply-To: Haydee Cooper <[log in to unmask]>
Date: Sunday, October 21, 2012 6:19 PM
To: "[log in to unmask]" <[log in to unmask]>
Subject: [VADCFLL-L] NXT brick error code 1

The Mindstorms software is giving an error code 1 (unknown error) and refusing to download the kids' program. The little diagnostic window says the NXT brick is unavailable. Restarting the software and the computer does nothing. Is there a patch for this?
 
Thank you,
 
Haydee
 
 

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