Trying to get the below code to work. It just creates a string of hex values from the users full name so that it can be put into Office and the user not get prompted. There is something wrong with me Execute statements as I always get a 'missing comma' error for the line right after the first execute. Any suggestions?

Code:
$UserName = @FullName
If Len ($UserName) > 0
   For $x=1 to 30
      $null=Execute('$userchar'+$x+'=LCase(DecToHex(ASC(SubStr('+$UserName+','+$x+',1)))))'
      $null=Execute("$$username=$username+$userchar$x+'00'"
   Next
Endif