Error writing file: { [Error: EMFILE: too many open files

[jiji262]

when I use this module, an error occurs:

Running "karma:debugrun" (karma) task
23 03 2016 10:43:15.524:ERROR [preprocessor:less]: Error writing file: { [Error: EMFILE: too many open files, open 'XXXXX\index.compiled.css']
  errno: -4066,
  code: 'EMFILE',
  syscall: 'open',
  path: 'XXXXX\\index.compiled.css' }
Error: EMFILE: too many open files, open 'XXXXX\index.compiled.css'
  at Error (native)