How User Power Shell in CRM Server?? - Create a New Key

Hello everybody!

I've asked somes post agos "How Configurate Email Sending with http web" and there was this two steps of answer:

1. On the CRM server, create a new key called 'AllowCredentialsEntryViaNonSecureChannels' and set it to 1
   
   
2. then, on the CRM Server, run this Powershell script:
   

   Add-PSSnapin Microsoft.Crm.PowerShell
   $setting = Get-CrmSetting ServerSideSyncEmailSettings
   $setting.AllowCredentialsEntryViaNonSecureChannels=$True
   Set-CrmSetting $setting
   Get-CrmSetting TraceSettings
   
   
   But I enter in PowerShell and it gave me an error, I've made a search about that and everyones has the same script....
   So, How I'ld use PowerShell to make that? Can Show with Photos?