A new two-axis positional error detection algorithm for probe storage is proposed : Using only probes, this algorithm can detect two-axis positions simultaneously and continuously for off-track control and synchronization. Two decomposition signals are multiplied to the probe readback signal while vibrating the scanner in low frequency of the specific value to extract two position error signals from it. In addition, the same algorithm using only one decomposition signal is proposed. Because this algorithm provides very precise positional errors continuously, off-track and synchronization errors can be controlled to zero continuously, and the sensitivities to disturbances can be reduced.