To send an IM to someone that you have not added to your Messenger List:

1. Click the "Actions" menu in Yahoo! Messenger and select "Send an Instant Message."
2. Double-click the ID of the person you wish to send a message to.
3. Type your message.

Note: If you enter an ID that does not exist, you will receive the following error message: "The message for user 'username' was not saved. Please verify the recipient's name and try again. Thank you."

To send an IM to a contact that you have added to your Messenger List:

1. Double-click the contact name.
2. Type your message.

Note: You can send an IM to a person who is offline. The next time the person comes online, your message will pop up automatically.