cnpm install webpack --save-dev Install fail!

Question

cnpm install webpack --save-dev

× Install fail! TypeError: Cannot convert undefined or null to object
TypeError: Cannot convert undefined or null to object
    at resolve (C:\Users\Administrator\AppData\Roaming\npm\node_modules\cnpm\node_modules\npminstall\lib\download\npm.js:44:40)
    at next (native)
    at onFulfilled (C:\Users\Administrator\AppData\Roaming\npm\node_modules\cnpm\node_modules\co\index.js:65:19)
    at process._tickCallback (internal/process/next_tick.js:109:7)
npminstall version: 3.2.1
npminstall args: C:\Program Files\nodejs\node.exe C:\Users\Administrator\AppData\Roaming\npm\node_modules\cnpm\node_modules\npminstall\bin\install.js --china --userconfig=C:\Users\Administrator\.cnpmrc --disturl=https://npm.taobao.org/mirrors/node --registry=http://registry.npm.taobao.org webpack --save-dev