用npm安装webpack 时出错！

Question

0 info it worked if it ends with ok
1 verbose cli [ 'D:\nodejs\node.exe',
1 verbose cli 'D:\nodejs\node_modules\npm\bin\npm-cli.js',
1 verbose cli 'install',
1 verbose cli 'webpack',
1 verbose cli '-g' ]
2 info using npm@3.10.10
3 info using node@v6.10.2
4 silly loadCurrentTree Starting
5 silly install loadCurrentTree
6 silly install readGlobalPackageData
7 silly fetchPackageMetaData webpack
8 silly fetchNamedPackageData webpack
9 silly mapToRegistry name webpack
10 silly mapToRegistry using default registry
11 silly mapToRegistry registry https://registry.npmjs.org/
12 silly mapToRegistry data Result {
12 silly mapToRegistry raw: 'webpack',
12 silly mapToRegistry scope: null,
12 silly mapToRegistry escapedName: 'webpack',
12 silly mapToRegistry name: 'webpack',
12 silly mapToRegistry rawSpec: '',
12 silly mapToRegistry spec: 'latest',
12 silly mapToRegistry type: 'tag' }
13 silly mapToRegistry uri https://registry.npmjs.org/webpack
14 verbose request uri https://registry.npmjs.org/webpack
15 verbose request no auth needed
16 info attempt registry request try #1 at 12:53:45
17 verbose request id 9de94cad0277d3c5
18 http request GET https://registry.npmjs.org/webpack
19 info retry will retry, error on last attempt: Error: unable to verify the first certificate
20 info attempt registry request try #2 at 12:54:01
21 http request GET https://registry.npmjs.org/webpack
22 info retry will retry, error on last attempt: Error: unable to verify the first certificate
23 info attempt registry request try #3 at 12:55:01
24 http request GET https://registry.npmjs.org/webpack
25 silly fetchPackageMetaData Error: unable to verify the first certificate
25 silly fetchPackageMetaData at Error (native)
25 silly fetchPackageMetaData at TLSSocket. (_tls_wrap.js:1092:38)
25 silly fetchPackageMetaData at emitNone (events.js:86:13)
25 silly fetchPackageMetaData at TLSSocket.emit (events.js:185:7)
25 silly fetchPackageMetaData at TLSSocket._finishInit (_tls_wrap.js:610:8)
25 silly fetchPackageMetaData at TLSWrap.ssl.onhandshakedone (_tls_wrap.js:440:38)
25 silly fetchPackageMetaData error for webpack { Error: unable to verify the first certificate
25 silly fetchPackageMetaData at Error (native)
25 silly fetchPackageMetaData at TLSSocket. (_tls_wrap.js:1092:38)
25 silly fetchPackageMetaData at emitNone (events.js:86:13)
25 silly fetchPackageMetaData at TLSSocket.emit (events.js:185:7)
25 silly fetchPackageMetaData at TLSSocket._finishInit (_tls_wrap.js:610:8)
25 silly fetchPackageMetaData at TLSWrap.ssl.onhandshakedone (_tls_wrap.js:440:38) code: 'UNABLE_TO_VERIFY_LEAF_SIGNATURE' }
26 silly rollbackFailedOptional Starting
27 silly rollbackFailedOptional Finishing
28 silly runTopLevelLifecycles Finishing
29 silly install printInstalled
30 verbose stack Error: unable to verify the first certificate
30 verbose stack at Error (native)
30 verbose stack at TLSSocket. (_tls_wrap.js:1092:38)
30 verbose stack at emitNone (events.js:86:13)
30 verbose stack at TLSSocket.emit (events.js:185:7)
30 verbose stack at TLSSocket._finishInit (_tls_wrap.js:610:8)
30 verbose stack at TLSWrap.ssl.onhandshakedone (_tls_wrap.js:440:38)
31 verbose cwd D:\
32 error Windows_NT 10.0.14393
33 error argv "D:\nodejs\node.exe" "D:\nodejs\node_modules\npm\bin\npm-cli.js" "install" "webpack" "-g"
34 error node v6.10.2
35 error npm v3.10.10
36 error code UNABLE_TO_VERIFY_LEAF_SIGNATURE
37 error unable to verify the first certificate
38 error If you need help, you may report this error at:
38 error https://github.com/npm/npm/issues
39 verbose exit [ 1, true ]