I reported this bug on ICU (Windows versions) to Apple in June 2011. With the following workarounds:
The workaround is this ....
Win XP
1) Close ICU
2) Delete the temp folder: c:\Documents and Settings\[username]\Local Settings\Temp\[AppName].app
3) Delete the deploy folder: c:\Documents and Settings\[username]\Application Data\AppleComputer\MobileDevice
4) Restart ICU. Drag in the App and install normally.
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Win 7
1) Close ICU
2) Delete the temp folder: c:\Users\[username]\AppData\Local\Temp\[AppName].app
3) Delete the deploy folder: c:\Users\[username]\AppData\Local\Apple Computer\MobileDevice\Applications\[AppName].app
4) Restart ICU. Drag in the App and install normally.
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