Which are you currently using to run the tool?
If you are locked out of the phone itself (not the SIM), you can try a factory reset, though this may delete your data. Sony Ericsson Vivaz U5 Phone Lock Code Reset Nov 10, 2010 YouTube·FastGSM
Yes, for a network/SIM lock you can purchase an unlock code and enter it directly on the phone. For a forgotten phone lock code, you can perform a hard reset using the key combination described above — no PC required.
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