How do I know if my messages have been delivered?

From the conversation timeline, you can quickly check the status of any message you've sent to your customers. Above each message you've sent, you'll see a little status indicator: 

Hover over the indicator to see when the message's status changed. There are several possible statuses here:

MESSAGE STATUS	ICON	MEANING
Sending...	n/a	Kayako is sending your message.
Failed		Something went wrong while sending your message. You'll have a chance to resend your message.
Not Sent		Your message has reached Kayako's API, but hasn't been sent to the customer yet.
Sent		Kayako has successfully sent your message to the customer.
Delivered		The customer has received your message, but they haven't read it yet.
Bounced		Something blocked the message from being accepted on the customer's end. NOTE: Hover over the symbol to see the specific error that caused the bounce.
Seen		The customer has opened your message.