[Android Q&A, Help & Troubleshooting] jjca:
Hi!

Yesterday, my device got crashed and I rebooted it. Now, it's stuck on boot logo. I did a little research in forums and other websites, the "solution" is to do a factory reset. So I decided to make a backup of my data first, since there's an option in my recovery for that.

I can enter to recovery mode, the default recovery, I chose "backup user data" and I get this error: "Cannot get phone encrypt state". I chose "system partition check" and got this: "System mount failed".

With this two errors, I decided to make a wipe without backing up my data, I made it without errors and I'm back to the beggining, stuck on boot logo.

Doing more research I decided to flash my device using SP Flash Tool v5. I used 4 different ROMs for my device, and nothing. I tried using "apply update from sdcard" in recovery mode and I get the same result. I can't use fastboot, I think my bootloader is locked, because when I write

fastboot flash recovery image
...

Nothing happens. Same with fastboot oem unlock.

My last option was to do a format, so I found a complete ROM and ran a Format All + Download, with same result again. I know, maybe I shouldn't have done the format BEFORE installing a custom recovery...

So, I installed TWRP, with it I can understand what is going on: TWRP's shell shows this:

Failed to mount /system (Invalid argument)
Failed to mount /cache (Invalid argument)
Failed to mount /data (Invalid argument)
Full SELinux support is present

Using TWRP tools to repair or change filesystems, the partition details for Data, System and Cache are:

Data: Present: NO, Size, Free, Used and Backup Size: 0MB, Removable: no. Type: ext4. Mount point /data

Cache: Present: NO, Size, Free, Used and Backup Size: 0MB, Removable: no. Type: ext4. Mount point /cache

System: Present: Yes, Size, Free, Used and Backup Size: 0MB, Removable: no. Type: ext4. Mount point /system

Dalvik/ART Cache: is an invalid partition selection

Internal Storage: Invalid partition selection.

Using shell:

$ cat /proc/partitions
major minor #blocks name
179 0 3795968 mmcblk0
179 1 1 mmcblk0p1
179 2 10240 mmcblk0p2
179 3 10240 mmcblk0p3
179 4 952320 mmcblk0p4
179 64 4096 mmclbk0boot1
179 32 4096 mmcblk0boot0

Using

$ fdisk /dev/block/mmcblk0
can't read from /dev/block/mmcblk0.

But:

fastboot getvar all
(bootloader) partition-size:fat: 493c0000
(bootloader) partition-type:fat: fat
(bootloader) partition-size:userdata: 31f00000
(bootloader) partition-type:userdata: ext4
(bootloader) partition-size:cache: e200000
(bootloader) partition-type:cache: ext4
(bootloader) partition-size:system: 3a200000
(bootloader) partition-type:system: ext4
(bootloader) partition-size:expdb: a00000
(bootloader) partition-type:expdb: raw data
(bootloader) partition-size:logo: 300000
(bootloader) partition-type:logo: raw data
(bootloader) partition-size:misc: 80000
(bootloader) partition-type:misc: raw data
(bootloader) partition-size:sec_ro: 40000
(bootloader) partition-type:sec_ro: raw data
(bootloader) partition-size:recovery: 600000
(bootloader) partition-type:recovery: raw data
(bootloader) partition-size:boot: 600000
(bootloader) partition-type:boot: raw data
(bootloader) partition-size:uboot: 60000
(bootloader) partition-type:uboot: raw data
(bootloader) partition-size:seccfg: 20000
(bootloader) partition-type:seccfg: raw data
(bootloader) partition-size:protect_s: a00000
(bootloader) partition-type:protect_s: ext4
(bootloader) partition-size:protect_f: a00000
(bootloader) partition-type:protect_f: ext4
(bootloader) partition-size:nvram: 500000
(bootloader) partition-type:nvram: raw data
(bootloader) partition-size:pro_info: 300000
(bootloader) partition-type:pro_info: raw data
(bootloader) partition-size:ebr1: 80000
(bootloader) partition-type:ebr1: raw data
(bootloader) partition-size:mbr: 80000
(bootloader) partition-type:mbr: raw data
(bootloader) partition-size:preloader: c00000
(bootloader) partition-type:preloader: raw data
(bootloader) kernel: lk
(bootloader) product: HUAQIN72_WE_72_B2_KK
(bootloader) version: 0.5
all: Done!!
finished. total time: 1.124s

I don't think that the partitions are deleted, I need to write in them.

I don't know what else to do, I think I have to rebuild partition table, but the problem is how to. Or, now I have an expensive paperweight :D

Thanks!!