IChat -8 Message

Question

My nephew away at college has my iMac 24 he has it set up in his dorm room using the university's wireless. He is able to iChat his Mom at her house where she has a iMac 20 with comcast and it works fine but she is the only one he can get through to on iChat. His brother (Mac Book), me at work (new iMac 20, using comcast), his friend in Texas (old iMac 20), and me at home (mac mini with iSight, and a MacBook, using comcast) can't ichat him. Everytime we try we keep getting the same -8 error message that I see posted all over this forum. All of us however can iChat each other he is the only one we can't. I have tried the different ports and the quicktime / bandwith suggestions to no success. I would think the problem is in the university's connection but then why would he be able to iChat his Mom with constant success. Sorry if I am long winded just wanted to set the stage the best I could. If any one has a new idea I am will to try it. We all can text chat fine its the audio and video thats the problem. Any help would be appreciated. Thanks. MIKE

Answer 1

Hi Shelco2,
Welcome to the Apple Discussion Pages.
Ummm A poser and no mistake.
I would look to how people have ports open in their routing devices.
iChat is unfriendly to use if it it goes through too many instances of NAT.
It can also be a bit funny about the way the devices on each end do NAT.
NAT is used to transfer the data coming from the Internet to the LAN side of your routing device be it modem or router or both.
Port forwarding remains the most common method of opening the ports.
UPnP (Universal Plug and Play) can certainly help as it does not rely so much on NAT (Network Address Translation)
Now if his mother is using UPnP and everyone else is not then this may be the area to look at.
IF this is not a common factor then look at additional features such as DOS (Denial of Service Protection) or SPI (Stateful Packet Inspection) or QoS (Quality of Service).
The first of these two protect you from suspicious contacts over the internet.
DoS works on cutting anything that looks like Too Much Data too Quickly coming to your computer. Stateful Packet Inspection in simple terms decides whether it should be going to your computer.
QoS is supposed to help VoIP connection but often gets in the way.
Basically his connection could be that much faster than before that he can send you lots of Data (possibly enough for 20 or 30 frames a sec of Video data which is much more than 15 fps).
I would adjust those settings that can be to be more tolerant or as the case with most devices turn them off.
Next I would check if everyone has done their Quicktime Setting
(System Preferences > Quicktime > Streaming set the drop down to 1.5Mbps)
Basically you seem to be running into the areas where iChat just seems to be plain quirky. Trying to find the issue that may be effecting everyone will be a needle in a haystack.
More likely is the fact that several issue may be causing different problem for each contact.
9:40 PM Monday; September 10, 2007