Applying a Category to a Message

A message can have a list of categories stored in the PidNameKeywords property (section To apply a new category to a message, the client MUST read the current value of the PidNameKeywords property from the message and check to see whether the current value already contains the name of the new category. If the current value does not include the name of the new category, the client MUST insert the name of the category in the list and set the new value of PidNameKeywords property on the message.