Error: Node Sass does not yet support your current environment: Windows 64-bit with false

This error message does not indicate a problem with Ionic, but rather with node-sass, which is specified to execute in your Gulp file.

The node-sass error:

Node Sass does not yet support your current environment

indicates that the version of node-sass you are trying to run is not compatible with the version of node installed.

Check the Node Sass release notes for the version of node-sass you have, to see which version of node is required.

If the version of node is wrong, you must downgrade node, or upgrade node-sass, until you have a compatible pair. If the node version is supported, you may just need to run:

npm rebuild node-sass

(with -g if node-sass was installed globally).

If that doesn't work, you can:

npm uninstall node-sass && npm install node-sass

(again, with -g if necessary).

This github issue has lots of more info on this.

npm uninstall node-sass && npm install node-sass is the better way to fix

Working for me only after installing Python 2.7.x (not 3.x) and then npm uninstall node-sass && npm install node-sass like @Quinn Comendant said.