function Create-RandomPassword 
( 
   [int] $minLength = 8, 
   [int] $maxLength = 8, 
   [bool] $useSymbols = $false, 
   [bool] $asSecureString = $false
) 
{ 
   [System.Security.Cryptography.RNGCryptoServiceProvider] $random = 
      new-object System.Security.Cryptography.RNGCryptoServiceProvider 
    
   # Get an array of all characters that can be used in the password 
   [string] $choice = Get-CharacterChoice -useSymbols $useSymbols 
    
   $randomPassword = $null 
   if (($minLength -le $maxLength) -and 
      ($minLength -ge 6)) 
   { 
      # Allocate a byte array of dimension 1 
      $randomNumber = new-object byte[] 1 
      if ($minLength -eq $maxLength) 
      { 
         [int] $length = $minLength 
      } 
      else 
      { 
         # Calculate a random length between minLength and maxLength 
         $random.GetBytes($randomNumber) 
         [int] $length = $minLength + $randomNumber[0] % 
                     ($maxLength - $minLength + 1) 
      } 
  
      # Allocate a byte array of dimension $length 
      $randomSequence = new-object byte[] $length 
      $hasUCase = $hasLCase = $hasNum = $false 
      while(!$hasUCase -or !$hasLCase -or !$hasNum) 
      { 
         # Generate random sequence of bytes 
         $random.GetBytes($randomSequence) 
          
         # Ensure that there is at least one number, uppercase 
         # character and lowercase character in the sequence. 
         $hasUCase = $hasLCase = $hasNum = $false 
         foreach($b in $randomSequence) 
         { 
            [char]$char = $choice[$b % $choice.Length] 
            if ($char -ge 'A' -and $char -le 'Z') 
            { 
               $hasUCase = $true 
            } 
             
            if ($char -ge 'a' -and $char -le 'z') 
            { 
               $hasLCase = $true 
            } 
             
            if ($char -ge '0' -and $char -le '9') 
            { 
               $hasNum = $true 
            } 
         } 
      } 
  
      if ($asSecureString) 
      { 
         $randomPassword = new-object System.Security.SecureString 
      } 
      else 
      { 
         [string] $randomPassword = '' 
      } 
       
      # Assign the password from the sequence of random bytes 
      foreach($b in $randomSequence) 
      { 
         [char]$char = $choice[$b % $choice.Length] 
         if ($asSecureString) 
         { 
            $randomPassword.AppendChar($char) 
         } 
         else 
         { 
            $randomPassword += $char 
         } 
      } 
   } 
    
   return $randomPassword 
} 

# Outputs an array of all the characters that the generated password 
# can be made up of. 
function Get-CharacterChoice 
( 
   [bool] $useSymbols = $true 
) 
{ 
   if ($useSymbols) 
   { 
      [string] $choice = '!"#$%&''()*+,-./' 
   } 
   else 
   { 
      [string] $choice = '' 
   } 
    
   $choice += '23456789' 
   if ($useSymbols) 
   { 
      $choice += ':;<=>?@' 
   } 
    
   $choice += 'ABCDEFGHJKMNPQRSTUVWXYZ' 
   if ($useSymbols) 
   { 
      $choice += '[\]^_`' 
   } 
    
   $choice += 'abcdefghjkmnpqrstuvwxyz' 
   if ($useSymbols) 
   { 
      $choice += '{|}~' 
   } 
    
   return $choice 
}