[Galaxy S II Q&A, Help & Troubleshooting] piduca2011:
First, sorry for my bad English. Hope I make myself clear enough for you to understand me.

Second, to the moderators: feel free to move this topic if I posted it on the wrong session. But as you will see reading the following, I believe that the issue I will describe is directly related with the Neatrom - correct me if I'm wrong, but I have reasons to believe that.

So, here it goes:

I have a Samsung Galaxy S2 (i9100), running XXLSJ Neatrom Lite v4.0, and this kernell: 3.0.31-Siyah-s2-v6.0b4+

In december 2012, I bought a MicroSD card (model Sandisk Ultra 32Gb class 10) to install in my i9100, and it rocks.

But 4 weeks ago, when I was playing some games on the phone, I ignored the first battery low warning messages, and kept playing to a point that the phone simply turned off. Completely. I recharged the battery and, after powering the phone on again, it showed a message saying something like "blank sdcard" or something. I had many pictures and important movies on that card, so I decided to not format it; instead, I searched for a way to fix it.

I tried to access the files from my computer - on Windows, no success; on Ubuntu, no success; on Mint, no success. Windows and Linux showed the icon representing the sdcard, but when I tried to open it under Windows, it showed a message saying "this disk is not formated. Do you want to format it?". Linux didn't show any message, and didn't opne a single window to show its content. Nothing. Nada.

Then, my cousin (a geek genius) took my card to test it on his own notebook. He made some long research on the net, and installed a software called TestDisk (http://www.cgsecurity.org/wiki/TestDisk - linux version) to try to recover the partition (or the MBR, I don't know exactly the tech name of this stuff...). He even entered on the software the number of cylinders, sectors and all that stuff to try to achieve sometuing... But after almost two hours reading tutorials, and trying hard to bring that card back to life with no success, he finally gave up, telling me to RMA the sdcard.

Then, I took the card from his hands, and put it aside, giving up too. Half an hour later, accepting the fact that my files was gone forever, I decided to try to format the card on my phone, to see if it would work after being formated. So, I put the card on the phone again, and powered the phone on... And, for my surprise, the card was back to life! For no reason, it decided to work again! With all the movies, all the pictures, all the games, everything was there, untouched!!!!

So, it worked great in the last 4 weeks, fast and nice - recording long HD movies, taking hundreds of pictures, installing huge data games, etc. It worked fine - until two days ago.

Because, two days ago, I was playing again, and again I ignored the low battery warnings, and it happened again! In the middle of the game, the battery ran out, and the phone turned off. Guess what? Yeah, after recharging it and turning it on again, there came that same message, telling me that my sdcard was blank! Again, no success trying to access it from Windows or Linux. And no geek cousin nearby... :(

(Of course, I had a backup of my files, created just after that first "death").

so, I sent an e-mail to my cousin, asking him about the software he used, and how it used it. He told me about that testdisk software. I downloaded the Windows version of the software, and give a try - no success. The program didn't recognize the drive letter of my "blank" sdcard, because the filesystem was simply not listed by the program. So, I went to the site, and I read that, under Linux, it was possible to force Testdisk to try to repair filesystems that was not shown in the list, by using a command line telling the software to look for the device through this mounting point (a folder inside /dev/). Linux stuff, I wont go any deep on this here.

So, I decided to restart my notebook, to boot on Linux to try that method. Guess what again? Suddenly, Windows recognized the sdcard again! I just ran the TestDisk utility, with no success - no command was used, I just ran the program, and since it didn't recognize the card, I closed the program. Nothing was done.

But, given the fact that the card was dead twice in the exact circumstantes (battery wearing completely off), and given the fact that the card came back to life after a simple run of the software TestDisk, I refuse to believe that it was a simple coincidence; I am not a geek, not a linux or android expert, nor a hardware wizzard, but my little experience tells me that it is possible that the android system locked the SDcard filesystem in a way that, after a sudden energy cut, it needed some sort of "logical shock" (made by TestDisk, even without any changes or command being called by the user, thats me).

I believe that this issue is part NeatRom's (or maybe kernell's) fault, because in stock roms, the system would close the app and close all sdcard access before turning the phone off to prevent issues like this one.

Again, I must repeat: I am not a technician, not an expert, so chances are I am wrong - very wrong. But I believe that my suspicions makes some sense, and woths to be investigated - or cleared out. And, of course, chances are that the card is deffective - and I already called RMA service from Sandisk. And I made another backup right now. But, I insist: everything is working: no movie corrupted, not a single file is corrupted... So, I still have a doubt here: was this issue cause by a deffective card, or was it cause by the sudden turn-offs?

Before you ask: no, I didn't test playing to the end of battery using another sdcard. By the way, I will never play to this point anymore. And yes, the card is still working!

Sorry for the VERY LONG POST. But I think that this testimonial may be of some value to the rom and kernell developpers.