The application is not installed on iPhone it requires newer version of iPhone os

HI...i have the Xcodes of 3.1.3 and 3.2.2 and 4.0 on my mac. i developed an application with project format - Xcode 3.1 compatible... my device's OS is 3.1.2 its .. when i tried to install the app, iTunes is showing the above message.开发者_Python百科 please tell me where would be the problem.

Thank in advance

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i set the iPhone OS Deployment Target to iPhone 3.0 in project settings

its worked fine..

Thank u