I have a trouble with npm and I haven\'t found solution in web.
Today I wanted to start my adventure with nodejs, npm, bower etc.
I use Windows 8.1.
I know this is an old question but i am adding this answer just for the record.
I was facing a similar issue i.e. rotating character with no progress in actual installation after trying to install using the following command on linux Mint 17(from http://bower.io/#install-bower):
npm install -g bower
The command which actually worked for me is:
npm install --global bower
Note: You will need root/administrative privelage to run this command. So you might wanna use sudo.