Unspecified Error occured while adding User in Client

Unspecified Error occured while adding User in Client

Hey there, i want to use the Manager to add local Admins on all Clients of the Domain,

if i use the the local User Manager and click in "create users" i get this error.
but if i use now the "get local users" button i see the user i wanted to create in the list

and if i use the net user command on the client i see that he created the user as a gast
 
does anyone know wheres the problem ? i run the tool on the DC so there should be no problem with the permissions.
                New to ADManager Plus?

                  New to ADSelfService Plus?