This week's book giveaway is in the General Computing forum. We're giving away four copies of Arduino in Action and have Martin Evans, Joshua Noble, and Jordan Hochenbaum on-line! See this thread for details.
You get this error because the WAR file you're trying to look at (BootstrapWAR.war) is not in the current directory. On which operating system is this? Note that some operating systems (such as Linux or Unix) are case-sensitive.
By the way "tvf" does not extract the war - it only lists the files in the war. To extract it, use "xvf".