Messages won't send from @mac.com emails?

i'm running on 10.7.3, messages new 10.8 app figured here place post.

wondering why keep getting error message upon trying receive messages "@mac.com" email address (signed icloud, btw), don't when use regular "@gmail.com" address.

 

username@mac.com working me. icloud username since migrated mobileme. worked first try after installed message.

 

Forums Macs macOS Older OS X Versions OS X Mountain Lion (10.8)

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