Samsung SPH-L720 Galaxy S4 (Samsung Altius) Supported Repairing bricked Samsung L720 is easy with the RIFF Box.

Phone is auto powered on with USB Data Cable connected to the PC while
battery is inserted. Please note, battery must be charged. If battery is
not charged enough there is chance of getting 0×42 error during
connection stage.

To resurrect Samsung L720:

•  Solder JTAG cable to Samsung L720 JTAG pads;


•  Connect USB cable or instert batteryu;


•  Make sure Samsung L720 is selected in the list of models;


•  Click Resurrect button;


•  Wait till software signals a successful operation completion;


•  Disconnect power supply, de-solder JTAG wires;

Now phone is in bootable condition, that is, even if it does not
start up normally, you can flash it using known flashing methods.

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