Question [Q] 4.1.1 device detected in device manager but not in command prompt

THE DEVICE penta ws 708 c is detected in disk manager .even name and driver version displayed.

pdanet 3.02 installed and operating fine.when adb command is used in command prompt it runs fine.
but when adb devices command is run it shows under list of devices no name or number .

so also when backup command is run it says -adb unable to connect to the device. what needs to be done?
SDK IS UP TO DATE with ECLIPSE STARTING UP AND RUNNING AND PLATFORM TOOLS UPDATED> PLEASE CLICK ON ATTACHMENTS AND SEE IF YOU CN FIND ANY PROBLEMS THERE.
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