PM EntityFramework -Version 6.0.0-alpha1 -Pre The term EntityFramework is no

hi when install EntityFramework -Version 6.0.0-alpha1 -Pre in asp.net

i see this error

PM> EntityFramework -Version 6.0.0-alpha1 -Pre The term 'EntityFramework' is not recognized as the name of a cmdlet, function, script file, or operable program. Check the spelling of the name, or if a path was included, verify  that the path is correct and try again. At line:1 char:16 + EntityFramework <<<<  -Version 6.0.0-alpha1 -Pre     + CategoryInfo          : ObjectNotFound: (EntityFramework:String) [], CommandNotFoundException     + FullyQualifiedErrorId : CommandNotFoundException

whats problem for me?