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original question:

I am trying to install monaca with this command.

npm install -g monaca

But right after getting these errors:

npm WARN checkPermissions Missing write access to /usr/local/lib/node_modules 

npm ERR! path /usr/local/lib/node_modules

npm ERR! code EACCES

npm ERR! errno -13

npm ERR! syscall access

npm ERR! Error: EACCES: permission denied, access '/usr/local/lib/node_modules'

npm ERR!  { Error: EACCES: permission denied, access '/usr/local/lib/node_modules'

npm ERR!   stack: 'Error: EACCES: permission denied, access '/usr/local/lib/node_modules'',

npm ERR!   errno: -13, npm ERR!   code: 'EACCES',

npm ERR!   syscall: 'access',

npm ERR!   path: '/usr/local/lib/node_modules' }

Any idea how to solve this problem?
Thank you