Acer tab model a5301

Wait for phone…
Phone found! [ 4 ]
Sync…
Inital Boot Ok!
BB_CPU_PID : 6580
BB_CPU_NME : [MediaTek] MT6580_S00
BB_CPU_EXT : 0xCA00 , 0x8A00 , 0x0000
Processing BROM stage
Settings for BROM configured!
SecCfgVal : 0x00000000
BromVer : 0x00FF
BLVersion : 0x0001
PreLoader : Active [ Boot with PL ]
BootLdrSS : NORMAL with SPRELOADER
Processing DA stage
DA Select done, will use MTK_AllInOne_DA_v5.1552.01.01
Sending and initialize DA …

[DA_ERROR] : SECURITY_BOOT_NOT_ACCEPTED
Boot Error!