That's the right solution !
Write the stringin Unicode ...
But how can I translate a ASCI string to Unicode ?
I would like "dynamically" translate the logged-in user to the $rc=WriteValue
("HKEY_CURRENT_USER\Software\Microsoft\Office\11.0\Common\UserInfo","UserName","THE_LOGGED-IN_USER","REG_BINARY")

Can yoy help me with this ?
Thanks