Usage: %ws modifiers switch accountname Where "accountname" can be the name or domain ame of the target computer or user ...

Usage: %ws [modifiers switch] [accountname] 
  Where "accountname" can be the name or domain
ame
  of the target computer or user account

  Edit Mode Switches:
   -R = reset HOST ServicePrincipalName
    Usage:   setspn -R accountname
   -A = add arbitrary SPN  
    Usage:   setspn -A SPN accountname
   -S = add arbitrary SPN after verifying no duplicates exist
    Usage:   setspn -S SPN accountname
   -D = delete arbitrary SPN
    Usage:   setspn -D SPN accountname
   -L = list SPNs registered to target account
    Usage:   setspn [-L] accountname   

  Edit Mode Modifiers:
   -C = specify that accountname is a computer account
   -U = specify that accountname is a user account
   
    Note: -C and -U are exclusive.  If neither is specified, the tool
     will interpret accountname as a computer name if such a computer
     exists, and a user name if it does not.

  Query Mode Switches:
   -Q = query for existence of SPN
    Usage:   setspn -Q SPN 
   -X = search for duplicate SPNs
    Usage:   setspn -X 

    Note: searching for duplicates, especially forestwide, can take
     a long period of time and a large amount of memory.  -Q will execute
     on each target domain/forest.  -X will return duplicates that exist
     across all targets. SPNs are not required to be unique across forests,
     but duplicates can cause authentication issues when authenticating
     cross-forest.

  Query Mode Modifiers:
   -P = suppresses progress to the console and can be used when redirecting
    output to a file or when used in an unattended script.  There will be no
    output until the command is complete.
   -F = perform queries at the forest, rather than domain level
   -T = perform query on the speicified domain or forest (when -F is also used)
    Usage:   setspn -T domain (switches and other parameters)
     "" or * can be used to indicate the current domain or forest.

    Note: these modifiers can be used with the -S switch in order to specify
     where the check for duplicates should be performed before adding the SPN.
    Note: -T can be specified multiple times.