It seems computer has established connection with openSDA jlink. But openSDA jlink can not access K64. I think there are few cause for this problem:
1. If you didn't cut j8/j11/j12 before, you can use a standalone jlink to check if K64 is ok.
2. If K64 is not ok, please check the power supply.
3. If K64 is ok, then maybe openSDA has problem. Can you tell me your Windows version and openSDA version?