How do I disable iMessage on every computer I installed with my email address? I have two multiple Macs. 2 Macbooks and an iMac. I installed El Capitan on all of them, with my one iTunes account.

The issue I am running into is that whenever I get a message on iMessage, it shows up on all computers and my iPad...not just my iPhone (and my Macbook) -- which is what I want.

How do I fix that?
Though I don't believe there's any way to do a broad-sweep method, you can disable it on a case-by-case basis on OS X and iOS.

OS X

Open the Messages app, then in the menu bar hit Messages -> Preferences. Click on the Accounts button, then your iMessage account in the sidebar. Uncheck the box labeled "Enable this account."



iOS

Go to Settings -> Messages and turn iMessage off.