```ruby
class Silverlight < Cask
  url 'http://silverlight.dlservice.microsoft.com/download/B/A/9/BA94BEC9-5DBC-4B50-BC2B-046A42399067/30214.00/Silverlight.dmg'
  homepage 'http://www.microsoft.com/silverlight/'
  version '5.1.30214.0'
  sha256 '4b9354d60451b033b4d6695b8d94d8f88663cc8d0b25cebda08b6b4fb0069cba'
  install 'Silverlight.pkg'
end
```

Update Silverlight to version 5.1.30317
user
```ruby
class Silverlight < Cask
  url 'http://silverlight.dlservice.microsoft.com/download/D/6/6/D66CF013-1021-437B-9A65-983871CCB3E6/30317.00/Silverlight.dmg'
  homepage 'http://www.microsoft.com/silverlight/'
  version '5.1.30317.0'
  sha256 'a425c522f84c8c3b2bcfb5f40abab0f8d67733f824be5c0e383819d06f230007'
  install 'Silverlight.pkg'
end
```
assistant