12-17-2012 12:26 PM
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As Desktop Software is unable to detect your device so you have to use the Application loader to force the detection and load the OS back on your device.But in this process you will lose all data within your device ,For further Instruction read this Knowledge base :
KB10144 : How to force the detection of the BlackBerry smartphone using Application Loader.
Additional Information : KB27157 : "Error 505", "App Error 505", or "JVM 505" appears on the BlackBerry .
So please try it and let us know of your progress.