My pc doesnt recognize the BBB with the MicroSd, Whats happening?

If i connect the BBB without the MicroSD (With the Angstrom Image on it) , it just recognize him as ARM335X USB. if i connect it with the SDcard , boots normally.

Sounds like you may have trashed the eMMC information. You might try reflashing the eMMC.

http://circuitco.com/support/BeagleBoneBlack

Gerald