unable to verify the first certificate when running npm install

I'm was looking at the Angular2 tutorial on:https://github.com/angular/quickstart/blob/master/README.md

However, when I run the npm install as per the guide, i initially got an error related to UNABLE_TO_VERIFY_LEAF_SIGNATURE.Which on googling seemed related to SSL cert so I then attempted to just get around this by using the following command:

npm config set strict-ssl false

I then retried npm install

This got a bit further but then got new errors related to "unable to verify the first certificate":

typings ERR! message Unable to connect to "https://api.typings.org/entries/dt/core-js/tags/0.0.0%2B20160725163759"typings ERR! caused by unable to verify the first certificatetypings ERR! cwd c:\Code\Angular2\Quickstarttypings ERR! system Windows_NT 6.1.7601typings ERR! command "C:\\Program Files\\nodejs\\node.exe" "c:\\Code\\Angular2\\Quickstart\\node_modules\\typings\\dist\\bin.js" "install"typings ERR! node -v v6.7.0typings ERR! typings -v 1.4.0typings ERR! code EUNAVAILABLEtypings ERR! If you need help, you may report this error at:typings ERR!   <https://github.com/typings/typings/issues>npm WARN optional Skipping failed optional dependency /chokidar/fsevents:npm WARN notsup Not compatible with your operating system or architecture: fsevents@1.0.14npm WARN angular-quickstart@1.0.0 No license field.npm ERR! Windows_NT 6.1.7601npm ERR! argv "C:\\Program Files\\nodejs\\node.exe" "C:\\Program Files\\nodejs\\node_modules\\npm\\bin\\npm-cli.js" "install"npm ERR! node v6.7.0npm ERR! npm  v3.10.3npm ERR! code ELIFECYCLEnpm ERR! angular-quickstart@1.0.0 postinstall: `typings install`npm ERR! Exit status 1npm ERR!npm ERR! Failed at the angular-quickstart@1.0.0 postinstall script 'typings install'.npm ERR! Make sure you have the latest version of node.js and npm installed.npm ERR! If you do, this is most likely a problem with the angular-quickstart package,npm ERR! not with npm itself.npm ERR! Tell the author that this fails on your system:npm ERR!     typings installnpm ERR! You can get information on how to open an issue for this project with:npm ERR!     npm bugs angular-quickstartnpm ERR! Or if that isn't available, you can get their info via:npm ERR!     npm owner ls angular-quickstartnpm ERR! There is likely additional logging output above.npm ERR! Please include the following file with any support request:npm ERR!     c:\Code\Angular2\Quickstart\npm-debug.log

I'm new to NodeJS and Angular2 development. Any ideas ?If I have missed out any detail then let me know.