My Apple Software Updater now works (almost) perfectly and I just successfully downloaded and installed itunes 10.6.3.25 through it!!! I actually figured out how to make it work(well sort of). I appreciate any insight that can be provided so that I can get my user's PC back to fully operational. The iTunes client update in question is 10.6.0.40 > 10.6.3.xx (most recent version). The only thing that I can think of in terms of causation is that a fully up-to-date iPhone 3GS was docked with this PC and that there may have been a conflict between the iPhone and the out-dated iTunes client software. My next step, if I am unable to find a less-destructive solution, is to de-authorized this iTunes client and tear out / reinstall all Apple software on this machine. The problem machine has been restarted countless times during this troubleshooting session. I have confirmed that all Windows Updates are installed. I have updated both video and audio drivers. I have gone through the MSCONFIG utility and disabled all start-up items AND services to remove potential software conflicts. I have tried the various updating methods in Windows Safe Mode. I have repeated this same behavior across multiple user accounts, too. BUT the various panes that typically list out the updates (with check boxes, etc.) are completely empty.

When I open up the Apple Software Update application, the app shows a brief status bar and then displays text to the effect that there are new updates to download. Sometimes the iTunes client will lock up upon checking for updates, but that is not consistent behavior. I have repeated this issue several times across multiple administrator-level accounts on this particular Windows machine. If I press the 'download' button, the dialog box closes and *nothing* else happens. Within iTunes, in both regular and 'safe-mode', I can successfully choose Help Menu > Check for Updates and I get all of the way to the dialog box w/the choice to either download the update or 'don't download' the update. Specifically, using either the iTunes client or the Apple Software Update application, I am unable to update Apple software.

Actually, I am also experiencing a scenario where the Apple Software Update application ( Windows 7 Home, 64-bit) is not working.

Apple software update not working