Messages Screen Sharing

Question

Messages won't allow me to share my screen or to request to share someone else's. I'm tyring to do it with my wife's computer running 10.8 on a separate network and the option is greyed out in the dropdown. I've ensured that Screen Sharing is enabled within messages and in the system preferences "sharing" pane.
We are both running 10.8 and using iMessage. We were both able to before the upgrade.
Any suggestions?
Thanks for your help.

Answer 1

Hi,
That one is so good it's wrong   needs modifying.
You do not have to have System Preferences > Screen Sharing Enable at all.
That is for a totally different app that is in the OS  and can be activated from the Finder.
In the Finder > Go Menu > Go to Server
Type in VNC:// and then IP of a LAN based computer  (Such as any Bonjour computer)
This will then Invoke the Screen Sharing App and link your with a VNC connection and show your their Desktop (if they accept).
You can do it to a Public IP (The modem of a contact) but they need to Forward the Port the VNC connection is On to their Computer.
This Process does use the Apple Remote Desktop engine the same as iChat/Messages does.
However iChat/Messages  makes the connection using SIP (Session Initiation Protocol) which deals with the routing through the Modem and any router at the other end an adds a VNC connection Along side and Audio Only chat.
It should read like this:-
Additions in italics.  Strike throughs for not needs action/text
• Go to your Apple Logo / System Preference / Sharing
• On the mac(s) that you would like to screen share , Turn on Screen Sharing. Allow Access / All Users  Not needed
• Open iMessage app on your mac
• iChat Style Buddy Lists are not displayed in iMessage by default. You will notice that there is no Screen Sharing button on iMessage as it was on iChat.   There is (a Button) on the Buddy lists.
• To activate it, go to the ‘Messages’ menu at the top menu bar and select Accounts and turn on ‘ Bonjour ‘
In fact Enable any Jabber or AIM valid Account  It does not have to be just Bonjour
• Once you turn on Bonjour Any Enabled Account you will notice the Bonjour name shows up at the bottom left hand corner of the iMessage window.
• Now under the Window tab, click on "Buddies" or COMMAND + 1 ( number 1 )
• You will now see the an iChat Style Buddy list pop up but any Bonjour only list may be empty.
This List is a combined list at present.
Go to Mesages Menu > Preferences > General Section and untick the line about "gathering all accounts"
• If you have not added an AIM or Jabber based Account do this:-
Messages menu again and under Preferences, go into ACCOUNTs and click on the + at the bottom corner and add an AIM or Jabber account .
Note : you will need an AIM/Jabber/Google account ( just like you did on iChat before )
• Once you log in successfully, You’ll notice your list appears and you’ll see the familiar Screen Share button located at the bottom centre of the Buddy List window.
Now go to the Video Menu and Enable Screen Sharing at your end.
Text you Buddy that is using AIM Screen Names or a Jabber/Google/Facebook ID on iChat or Messages and get them to enable Screen Sharing as well.
To activate, simply click on it and it will send them a request.
Alternatively Highlight the Buddy and use the Buddies Menu
Alternatively to that Right click the Buddy and use the Contextual Menu.
NOTE:-
Screen Sharing like Audio Only chats and Video Chats is AIM to AIM (including Valid Apple ID options) or Jabber to Jabber (which includes GoogleTalk and Facebook IDs) using iChat or Messages on both computers.
11:25 PM      Thursday; February 21, 2013
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