How do I get Share my Screen to work?

Question

I'm trying to share my screen iMac to MacBook. Both on Mountain Lion. Under the VIDEO drop down Screen Sharing on both computers is checked off. In SYSTEM PREFERNCES > SHARING, Screen Sharing is on. Yet, I cannot share my screen, or share the screen of my friend via Messages.
ANY IDEAS HOW TO FIX???

Answer 1

HI,
The @me.com, the GoogleTalk and Bonjour accounts should all be able to do Screen Sharing in Messages.
The other end does have to be using either iChat or Messages as well.
It does need to be On at your end but does not have to have the System Preferences > Sharing option Enabled (Uses the same engine (Apple Remote Desktop) only)
It may pay to go to the General section of the Preferences for the App and Untick the line that gathers the 3 Buddy List in to one.
Then highlight each Buddy List in turn and then check the Video Menu > Screen Sharing again as it may be an issue with one account that is crossing over when they are linked.
The next reason could be your Internet Speed.
Messages "measures" this at the app start up
It can get "confused" as to the speed if you have it starting up at the same time as the Mac because of the things the OS does in starting up and creating the Internet connection.
Also check Messages Menu > Preferences > Video section > Bandwidth Limit.
This should not be set at the 200kbps (it is too close to the minimum of 128 needed for the Screen Sharing if your service varies)
Of course it could be your service is too slow.
9:10 PM      Sunday; September 9, 2012
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