then your only option will be to Force Quit the installer.
Once you have done that, and before you attempt to launch iTunes, make a copy of the iTunes folder. (if you have disk space available)
Then launch iTunes. You will almost certainly have to run that update again
P
I own an iMac running Mac OS X 10.4.11 and am upgrading iTunes to version 9.2 using Apple Software Update, but it is stuck on "Installing Apple Mobile Device Support" and not making ANY progress. I thought about force quitting Apple Software Update, but am afraid that iTunes would not work correctly. I would really appreciate any help!

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