I have an imac G5. I have opened an account with streamguys.com to
broadcast live video over the net via quicktime broadcaster, automatic
unicast(announce) with correct settings and correct password etc (I
triple checked with streamguys.com) I get a Precondition Failed Error
412 message when I click to broadcast. I can find no clear information
on this. What can I do to get this working?

This error is coming from Quicktime (not the fact your running a Mac)

From what Quicktime website says the problem is not a login issue but
a problem with somthing your client lacks (or the server is failing to
get). Now I know a G5 is a good computer so I doubt that it's a
hardware problem.

What it sounds like is a Internet Connection issue.
*What type of internet do you have?
->If you have dailup then likely your not able to reply to a request
in the handshake (setup of the broadcast) fast and your failing in
there.
 -> Solution: Get DSL or Cable
*You have a Firewall in a router or software
->It blocking the unicast setup in some way
 -> Solution: Ask the streamguys.com what ports need to be openned to
make this work, then edit your firewall to open the ports
->Your ISP gives you free virus protection and it's blocking your unicast setup
 -> Solution: Talk to your ISP and get them to open RTSP ports (they
should know if not talk to streamguys.com
->Your NAT is failing
 (What this is: NAT lets you put many "Local" address behided a single
"Real" Address, basic this is cheaper)
 -> Solution: If your getting internet from your landlord then buy
your own internet accout, otherwise talk to the people would make your
router/hub
-> Check if your MAC can take unicast
 ->This will be in the Network connection area you may need a plug in
or somthing for Unicast.

Hope this Helps

HI, thanks for the input... I should have added, however, that I had
it working fine when the streamguys set up a test feed for me. They
said they took that same test feed and kept everything the same for
the current feed. So same computer, same feed (same applications with
same settings etc) only now I get the 412 error....