Hi,
Two things. (first)
Go to the VIEW MENU of IChat and make sure both "Show" items for Video and AUdio are ticked (Selecting them Toggles them On or Off).
Go to the VIDEO MENU in iChat and do thje same for Camera Enabled an Microphone Enabled.
Next.
It wouild be useful to know if this is a Screen Name that Logs in to AIM (where there should not be a restriction to who you can video or Audio Chat to) or a Jabber based one (including GoogleTalk) where there are limits to who you can Video or Audio Chat to depeding what app they are using or if they are logged in to the Google Mail Page.
Your Post seems to imply AIM based connections based on the fact you got an Invite.
UPnP or Port Mapping Protocol or any other Method
iChat does need to have Firewall, if on, set up to allow Incoming connections to iChat.
The fact that you got the Pop Invite window suggests that it is.
System Preferences > Security > Firewall tab
Click the Advanced Button if On.
Make sure Allow Signed Apps is enabled and iChat is in the List
UPnP in most routers allows the App to tell the router which ports to allow.
Port Mappig Protocol on the Apple Airport Base Stations does a similar job.
In neither case do Ports have to be set.
There can be issues if your Modem routes as well. ( Double DHCP Server situation may exist)
Screen Sharing by iChat is defined as a Audio Chat + a VNC connection.
You cannot Screen Share if Audio and Video do not work through the firewall or Router (Video and Audio use the same ports with a double stream)
UPnP and Port Mapping Protocol are the only methods that allow Screen Sharing due to the VCN bit being on a random port.
If you use Port Forwarding to open Ports in your Router or Port Triggering this should not effects the icon status
iChat will video to other Jabber logins if they are using iChat as well.
They may not show the Green Video or Audio icons if:-
1) They are logged in to Google Mail's web page (where chat is) (web Browser chat - Intel Mac only with a Google Plug-in)
2) They are using the PC app called Google Talk.
3) Using any Jabber app on a Mac or a PC
Speed.
You do need to have Enough Internet Speed for iChat.
Open the VIDEO MENU and then the Connection Doctor item
Click on Capabilities.
This should tell you if iChat found enough speed when it was started up.
In Panther, Tiger and Leopard that was partly controlled by what was read from the System Preferences > Quicktime Setting and the iChat Menu > Preferences > Video Section > Bandwidth setting.
If set to 100kbps it will be too low for Video chats.
Test your Connection Speed
You should get at least 80% of what you pay for showing up here (you lose some to maintaining the connection and some to the test.) If you have a very fast connection of Mbps Upload then the percentage should be higher.
At the very least for "Real World" connections you should have 200kbps as an Upload.
Apple say the minimum is 128kbps for Video Chat. (You will get a Special Message if at the Video Chat invite sending iChat finds only 50kbps or less (dial up speeds))
iChat checks the Internet Speed it can see on launch and again when starting an Audio Only of Video chat.
The first can appear too low if the computer is starting up at the same time and the Internet Connection is not established.
What other apps and also what other computers (or Phones) are doing on your LAN can effect things as well.
9:07 PM Saturday; July 2, 2011
Please, if posting Logs, do not post any Log info after the line "Binary Images for iChat"
G4/1GhzDual MDD (Leopard 10.5.8)
MacBookPro 2Gb( 10.6.8)
Mac OS X (10.6.7),
"Limit the Logs to the Bits above Binary Images." No, Seriously
