Info I have the same error with any pcs of LT18, but I have unlocked too 2 units of Lt18 with Polar.
I installed Xperia Polar Drivers, and I unlocked any LT18 but with the same Drivers, Cable and POlar Software, canīt unlock other LT18.
I tryed with 2 differents Computer, with differents usb ports...etc
I think are any LT18 with differente security
Regards |