<p>The situation: I have a pieceofcrapuous laptop. One of the things that make it pieceofcrapuous is that the battery is dead, and the power cable pulls out of the back with little effort.</p>

<p>I recently received a non-pieceofcrapuous laptop, and I am in the process of copying everything from old to new. I'm trying to xcopy c:*.* from the old machine to an external hard drive, but because the cord pulls out so frequently, the xcopy is interrupted fairly often.</p>

<p>What I need is a switch in XCopy that will copy eveything except for files that already exist in the destination folder -- the exact opposite of the behavior of the /U switch. </p>

<p>Does anyone know of a way to do this? </p>

I find RoboCopy is a good alternative to xcopy. It supports high latency connections much better and supports resuming a copy.
References
Wikipedia - robocopy
Downloads
Edit
Robocopy was introduced as a standard feature of Windows Vista and Windows Server 2008.
Robocopy is shipped as part of the Windows Server 2003 resource kit and can be download from the
Microsoft download site
.
A very simple GUI has also been release for RoboCopy on technet
http://technet.microsoft.com/en-us/magazine/cc160891.aspx