Checking a valid user name of an account in Windows 7

hi

when creating account in windows 7, how check if user typed valid user name , if name exists on local computer?

thanks

bye

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balubeto

this started:

$user = "user"  $computer = "computer"  $colusers = ([adsi]("winnt://$c,computer")).children | ? {$_.psbase.schemaclassname -eq "user"} | select -expand name  if ($colusers -contains $user) {    "$($user) exists"    }

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