I changed my Apple ID and password on all my devices, moving from a Yahoo address to a Gmail address. Now, I can no longer see any messages on my Macbook Air. iMessage is enabled. Whenever i receive a text message, I can see it on my phone and iPad, but all I get on the Mac are notifications that I'm receiving texts and the same blank Message box I've had since I changed the ID three days ago. When I click on the notification that appears, it has no affect on the Message section – it remains blank . This started when I changed my Apple ID settings independently on each device (because I received a message that my password was being used elsewhere – the tech people later told me that sometimes your carrier's location is shown). The new ID and password are working on all the devices and everything appears to agree. Can anyone help solve the problem? Many thanks.