Phone number not registered with iMessage

I have 2 Macs (OS X 10.10.3) and one iPhone 5S (iOS 8.3)

Mac 1 sends iMessages OK, Mac 2 returns 'the phone number is not registered with imessage'

iPhone in my pocket.

How do I fix Mac 2 issue so I can iMessage with iPhone 5S and both Macs.
MARSPATHRetired EE/Computers/ITAsked:
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Ned RamsayNetwork Operations ManagerCommented:
Hi Marspath,
Try sending to your AppleID from MAC2, see if that works.
Do you receive messages on MAC2 ok? Is it registered with the same AppleID?

Justin BradshawOwnerCommented:
you'll want to sign out of iMessage on the iPhone first, then restart it and sign back in. That should add the phone number to the account. Then Mac2 should automatically add the number. If not, you can sign out and back in from there, too.

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MARSPATHRetired EE/Computers/ITAuthor Commented:
Setup OK using Messages Preferences and Verification. Thanks
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