[Patrick Chiang]

As the otherguy said, your master build.xml is probably broken. The surest way to test-fix this is to copy it over from another computer where deployment is working. If that is not possible, the stock file provided above should suffice.

The file is not directly accessible in Netbeans, but you can find its location by going into Tools > Options > Misc top tab > FRC config, and looking at the directory for "Use Alternate SDK Location".
You should find it in "C:\Users\[username]\sunspotfrcsdk\build.xml"