npm install -g npm ERR! Error: EPERM: operation not permitted, open

C:\Users\Srinivas>npm install -g bower
npm WARN deprecated bower@1.8.0: ..psst! While Bower is maintained, we recommend Yarn and Webpack for *new* front-end projects! Yarn's advantage is security and reliability, and Webpack's is support for both CommonJS and AMD projects. Currently there
's no migration path, but please help to create it: https://github.com/bower/bower/issues/2467
npm ERR! tar.unpack untar error C:\Users\Srinivas\AppData\Roaming\npm-cache\bower\1.8.0\package.tgz
npm ERR! Windows_NT 6.1.7601
npm ERR! argv "C:\\Program Files\\nodejs\\node.exe" "C:\\Program Files\\nodejs\\node_modules\\npm\\bin\\npm-cli.js" "install" "-g" "bower"
npm ERR! node v4.5.0
npm ERR! npm  v2.15.9
npm ERR! path C:\Users\Srinivas\AppData\Roaming\npm\node_modules\bower\lib\config.js
npm ERR! code EPERM
npm ERR! errno -4048
npm ERR! syscall open

npm ERR! Error: EPERM: operation not permitted, open 'C:\Users\Srinivas\AppData\Roaming\npm\node_modules\bower\lib\config.js'
npm ERR!     at Error (native)
npm ERR!  { [Error: EPERM: operation not permitted, open 'C:\Users\Srinivas\AppData\Roaming\npm\node_modules\bower\lib\config.js']
npm ERR!   errno: -4048,
npm ERR!   code: 'EPERM',
npm ERR!   syscall: 'open',
npm ERR!   path: 'C:\\Users\\Srinivas\\AppData\\Roaming\\npm\\node_modules\\bower\\lib\\config.js' }
npm ERR!
npm ERR! Please try running this command again as root/Administrator.

npm ERR! Please include the following file with any support request:
npm ERR!     C:\Users\Srinivas\npm-debug.log



Solution :
clean npm cache 

C:\Users\Srinivas>npm cache clean

Then try

C:\Users\Srinivas>npm install -g bower
npm WARN deprecated bower@1.8.0: ..psst! While Bower is maintained, we recommend Yarn and Webpack for *new* front-end projects! Yarn's advantage is security and reliability, and We
's no migration path, but please help to create it: https://github.com/bower/bower/issues/2467
C:\Users\Srinivas\AppData\Roaming\npm\bower -> C:\Users\Srinivas\AppData\Roaming\npm\node_modules\bower\bin\bower
bower@1.8.0 C:\Users\Srinivas\AppData\Roaming\npm\node_modules\bower