Iphone is invisible for computer

Hi All,

I have the strangest problem with my iPhone (2G). I can charge it with USB, but I cannot sync. My MBP doesn't see my iPhone. I tried on different pc's as well. (even windows) I tried reinstalling my iTunes, resetting the iPhone. and I tried the DFU mode. But none worked. When I plugin another iPhone it gets detected automatically within a few seconds.

Ps. I have jailbroken it with the PwnageTool. The software version is 1.x.

I hope someone has a clue.

Kind regards,
Jankees

 

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Doesn't anyone know?