Help E: failed to mount /cache

[maagaard]

Hi. I think I might have bricked my SGS2. Can anyone help me?
I have done the following:

Yesterday i flashed the new ICS 4.0.3 I9100XXLP2 on to my phone(using Odin). After having used that a bit and found it not to be working very well, i tried the older build I9100XXLP1. This had somewhat the same perfomance as the other one.

Today i decided to go back to the stock for more stability, so i flashed it with PDA:XWKI8| PHONE:NEKI2| CSC : DREKI1 (Danish 3 carrier branded).
This didn't work properly though. I never made it through the Configuration Manager setting up the phone, since it kept crashing.
I then tried to flash the PDA: XWKF4 Phone: NEKF2 CSC : DREKF1 (Also 3 carrier branded).

And this is where the problems started! Odin said the flash had finished with success, but on startup the phone never got past the Samsung boot logo, and it just hangs there.

I have tried going back to download mode, which is no problem at all, but odin wont recognize the phone anymore. I have tried on several computers, no luck. Also i cannot connect to it with ADB. I have also tried this on several computers including a Mac.

Getting the phone in recovery is a bit of a problem on the other hand. I cannot control whether or not to enter recovery mode. It seems to be more random than actually depending on what keys i press. Anyways it some times succeeds to enter recovery mode. This is what it looks like:

(Don't mind the cracked screen - it has been like that for 4 months)

Can anyone help me, or am I just screwed?

 

[Meiji]

Have you tried retiring the battery? If not, retire battery, sim and sdcard for some minutes (have a coffee, dinner, whatever), then place only the battery (without sim nor sdcard).. try again in Download Mode with a stable rom..

Good luck!! I'm sure there's still a solution =)

 

[Studleyson]

Hi, I have the exact same problem. Would you please be kind to reply?

If it did, could you link me the ROM you used?

 

[Archenique]

Have same problem with my SGS2 tried zylion times and still got same answer can't mount cache bla bla bla
Please can anybody help me

 

[Gearu]

Wipe Data/Factory Reset?
(with SDcard and SIM out)

 

[Sword Fish]

I often wonder when people say my phone got stuck in Samsung boot mode, how long did you wait? If you wipe your cache as most of the builds do, it can take upto 5 minutes for the system to boot up as it rebuilds the required cache files. Are people who brick there phones not waiting long enough?

 

[rigpig]

same problem here, has anyone got a solution for this please.

 

[javadeveloper]

I am stuck in the same situation. Can anyone please give some idea what to do?

Thanks in advance.

 

[Slug]

In this situation the best thing to do is a full wipe/factory reset. See here for how to do so.

 

[ykrugernl]

So I wanted to do a cache partition wipe, but my device had the TWRP boot menu I had totally forgotten about. Not sure where to do this wipe, I just went to Wipe / Advanced Wipe / Wipe cache.

This took very long compared to the stock android boot menu wipe. So (stupid me), I aborted the process by turning off the device.

Upon rebooting I got in the feared bootloop (where it doesnt go past the samsung logo).
Upon re-entering TWRP I went to the option to 'repair' the cache partition, where I got the error "Unable to mount /cache".
So what I did to fix it (assuming you have TWRP or another boot menu that supports the following function), was the option next to Repair: Format file system. I formatted the cache partition file system to the file system it was already using. "Format succesful!".

Booting up the device once again worked.

Hope this helps some of you.

 

[dynomot]

Yes TWRP will repair the cache. Although a full factory reset should do the trick as well.

I often wonder when people say my phone got stuck in Samsung boot mode, how long did you wait? If you wipe your cache as most of the builds do, it can take upto 5 minutes for the system to boot up as it rebuilds the required cache files. Are people who brick there phones not waiting long enough?

Yes, that is a common problem in my experience. I have recently "unrooted" and flashed a stock version of Lollipop to it, as to sell it. It took 7 minutes (I timed it) to reboot from switch on with the Samsung logo glowing and dimming, as it does in a bootloop proper, all that time. A bootloop lasts until the battery dies (they usually don't charge in a bootloop either), or you factory reset it, or even occasionally power down and reboot. I leave a seemingly bootlooping phone at least 15 minutes before calling it bootlooped.

 

[Hawker]

There are a couple of "bootloop" scenarios

1. Stuck on the initial "S[2,3,4,5,6]" logo screen
This is generally bad news which usually needs a re-flash of the ROM or CWM restore (or at the very least, a /system restore). To be stuck here means your kernel is not able to take control of your device.

2. Stuck on the ROM's boot animation screen.
To get here means your kernel has kicked in (the LED should be on if you have an S3 or later) but there is a problem with your ROM.

Either way, the course of action to undertake when encountering a bootloop is generally the same.....
Attempt the following, in this order:

1. Take out your battery then replace it. If your device powers up without touching the POWER button then you have a faulty POWER button and you will have to dismantle it to fix it.
2. If your POWER button is working correctly then perform a soft reset immediately followed by a hard reset:
a) Soft reset - take out battery and hold POWER+HOME for 10 seconds
b) Hard reset - replace battery and hold POWER+HOME for 10 seconds (until you see the screen turn off again)
3. Boot into recovery and wipe cache (+dalvik if rooted) then try booting up again
4. if no joy, try flashing another kernel or reflash your current kernel (.ko modules may be missing)....(if rooted)
5. If that didn't work, and you have an external SD card, take this out and reboot in order to rule this out as an issue.
6. if no joy, try flashing/reflashing your Recovery (Philz, TWRP etc), through Odin preferably....(if rooted)
7. still no joy, restore a CWM backup....(if rooted)
8. If you have no CWM backup, factory reset
9. If you get to here with no joy then tough tittianas I'm afraid. It's a full wipe and reflash firmware jobbie.​

Regarding wiping cache through recovery. This won't affect boot times at all. There is very little in the /cache partition (which is the only thing the cache wipe function in recovery actually wipes). Just take a look in Root Explorer for yourself if you don't believe me. The S4 PIT for example allocates a whopping 2Gb to this. Not 100% sure why its so big, but I think it must be due to possible swap-space used by the kernel.

On the very first boot of your ROM (after a factory reset), the boot animation takes a long time. This is because your ROM is building /sdcard/Android, /storage/extSdCard/Android and /data/data/[apps]/cache areas. This is what takes up most of the long boot time initially.
When you see the Android is upgrading, Optimising app xxx of xxx message, this is where dalvik-cahce gets built.

If you want further information, take a look at my thread below:
ROMBlitz

 

[dynomot]

Hawker, pounces in, and gives the definitive answer.

 

[COOPERAMISKI]

my android is stuck at boot logo ,its also shows this when i boot into recovery , it shows these messages when i boot into recovery it shows these messages the screen stuck on boot logo....
My phone wont boot , its stuck at the boot logo ,when i boot into cwm recovery too these errors pup up
cwm automade 21.09.2013 23:20:59
E:Can't mount /cache/recovery/command
E:Can't mount /cache/recovery/log
E:Can't open /cache/recovery/log
E:Can't mount /cache/recovery/last_log
E:Can't open /cache/recovery/last_log

I tried restoring my stock backup but these showed up
""checking MD5 sums...
Erasing boot before restore ...
Restoring boot image ...
Restoring system...
E:format _volume: make _extf4fs failed on /dev/block/mmcblk0p3
Error While formatting/system!""

mates pls help ...am at newbie with these stuffs.