SSMS: Restart the values on a IDENTITY field I am starting to use SSMS to manage a database and I am having a problem I would appreciate some help with. 

I have a table that was created with

CREATE TABLE [dbo].[Machine](
        [Machine_id] [int] IDENTITY(1,1) NOT NULL,
        [Machine_alias] [nvarchar](50) NULL,
        [Machine_ip] [nvarchar](50) NULL,
        [Machine_stockWarning] [int] NOT NULL,
    .....
CONSTRAINT [PK_machine] PRIMARY KEY CLUSTERED 
(
    [Machine_id] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]
GO


Then I tried to add a row manually and the Machine_id became 1, but there was something wrong with this line so I deleted it. 
Then I tried to add another row, but this time Machine_id is 2. How can I reinitiate the count so that it starts on 1 again?
DBCC CHECKIDENT('tablename',reseed,1)