Galaxy s2 will not connect to any pc

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http://forum.xda-developers.com – I just bought a galaxy s2 running stock gb on ebay and whenever I plug it in any pc it only charges. There is no usb notification nor does computer play a sound when the phone is connected. The phone makes a sound and just charges no matter what I do, I have tried usb debugging on/off and nothing. When I go into wifi/connection settings and select usb mode it says to connect a cable when the usb cable is already connected. I have tried many usb cables including the original samsung one. Did I just buy a defective phone or am I missing something? (HowTos)