[Samsung Epic 4G Touch] drnull:
Just to add a new data point to this data partition corruption mess, I'm in the same boat but have never used touch cwm. And sorry for the wall of text here...

For history, I've flashed a few different recovery/kernels over the past 6 months or so, but never a new rom. I've done Zedomax (back in the heavy LOS days) and Bubby and stock.

Once darchstar's CM9 testing build post came out, I thought that would be fun to try out so I got myself all backed up and started down the instructions.

So I went down the "First install of CM9" path:

BACKUP your existing ROM - check

Did you backup your existing ROM? No? BACK IT UP, GENIUS - heh, ok, I get it. Backed up and copied to my pc, you never know what might happen to that little sd card.

Reboot to DOWNLOAD mode (power+vol-down) - got it

Using ODIN (link) flash to StockCWM EL26. - following these instructions as I didn't want to brick, I flashed using ODIN 1.85, selecting PDA and leaving all the other boxes unchecked (i.e., Auto Reboot & PDA are the only boxes checked).

... ok, so far so good, it booted up and everything was fine still, of course...

Reboot to recovery (power+vol-up) - done

WIPE DATA - done, though I only did it once and didn't wipe cache (dalvik or other)

Flash CM9 - I had copied the zip to the sd card, so I choose this option in cwm and everything went fine.

Then things started going downhill. I rebooted after flashing CM9, and it stuck at the boot animation (the colored squares flipping around on the screen) for about 5 minutes. A reminder, at this point I haven't used any of the clear data options from the newly flashed CM9. It just wouldn't boot from the start. Ok, no biggie, I reboot back to CWM and decide to clear data/cache/dalvik everything I can find that looks fun to do.

This might be where I goofed. I'm guessing that when I booted back recovery, I was no longer on the stock CWM EL26 recovery. Now, I'm on the recovery that came with the CM9 rom, the one that we are specifically told not to use. Still - silly me (it was late!) - I did a format data, it took about 5 minutes, then I rebooted and it wouldn't even get into the boot animation.

After going through a few more reboots and wipes with no boot animations, I decide to attempt to get things back to a working state, so I reflash (odin) the stock cwm el26 recovery from earlier in the process and try to restore my backup I took. That fails with a "Error while restoring /data"

Ok, now I'm starting to worry a little. I look around and find one of sfhub's all-in-one odin/stock installers (SPH-D710.EL29_CL852097_ROOTED-oc-sfx.exe I think). I run that and it gets stuck at data.img. So I find this thread and read all the way through it.

Everybody is pointing the finger at a non-writable /data partition and touch cwm. But like I said wayyy up there at the top, I haven't ever used touch cwm. And to make it even weirder, if I install rogue cwm kernel (to get adb working) I could mount /data just fine and "touch" or "echo" to files in there all day long and they write just fine. Although now after playing with this for a few hours last night, I can't even mount /data anymore. Strange.

I've activated my old pre (well, my frankenpre2) just to have something but I really don't want to sit on it too long. Thing doesn't even feel like a smartphone anymore. :( I've got TEP and am getting the feeling I'll have to lie to the Sprint store to get out of this, but if anybody has any ideas for me to try I'm open to trying stuff.

I've got 15 years programming/unix experience, so I can throw anything at it that you can suggest.

Here's some output from the troubleshooting commands I've seen in this thread:

mount /data
mount: mounting /dev/block/mmcblk0p10 on /data failed: Invalid argument

cd /dev/block
/dev/block # l
l
drwxr-xr-x 3 root root 60 Jan 1 00:47 platform/
brw------- 1 root root 259, 1 Jan 1 00:47 mmcblk0p9
brw-rw---- 1 system radio 259, 0 Jan 1 00:47 mmcblk0p8
brw------- 1 root root 179, 7 Jan 1 00:47 mmcblk0p7
brw------- 1 root root 179, 6 Jan 1 00:47 mmcblk0p6
brw------- 1 root root 179, 5 Jan 1 00:47 mmcblk0p5
brw------- 1 root root 179, 4 Jan 1 00:47 mmcblk0p4
brw------- 1 root root 179, 3 Jan 1 00:47 mmcblk0p3
brw------- 1 root root 179, 2 Jan 1 00:47 mmcblk0p2
brw------- 1 root root 259, 4 Jan 1 00:47 mmcblk0p12
brw------- 1 root root 259, 3 Jan 1 00:47 mmcblk0p11
brw------- 1 root root 259, 2 Jan 1 00:47 mmcblk0p10
brw------- 1 root root 179, 1 Jan 1 00:47 mmcblk0p1
brw------- 1 root root 179, 16 Jan 1 00:47 mmcblk0boot1
brw------- 1 root root 179, 8 Jan 1 00:47 mmcblk0boot0
brw------- 1 root root 179, 0 Jan 1 00:47 mmcblk0
brw------- 1 root root 1, 9 Jan 1 00:47 ram9
brw------- 1 root root 1, 8 Jan 1 00:47 ram8
brw------- 1 root root 1, 7 Jan 1 00:47 ram7
brw------- 1 root root 1, 6 Jan 1 00:47 ram6
brw------- 1 root root 1, 5 Jan 1 00:47 ram5
brw------- 1 root root 1, 4 Jan 1 00:47 ram4
brw------- 1 root root 1, 3 Jan 1 00:47 ram3
brw------- 1 root root 1, 2 Jan 1 00:47 ram2
brw------- 1 root root 1, 15 Jan 1 00:47 ram15
brw------- 1 root root 1, 14 Jan 1 00:47 ram14
brw------- 1 root root 1, 13 Jan 1 00:47 ram13
brw------- 1 root root 1, 12 Jan 1 00:47 ram12
brw------- 1 root root 1, 11 Jan 1 00:47 ram11
brw------- 1 root root 1, 10 Jan 1 00:47 ram10
brw------- 1 root root 1, 1 Jan 1 00:47 ram1
brw------- 1 root root 1, 0 Jan 1 00:47 ram0
brw------- 1 root root 7, 7 Jan 1 00:47 loop7
brw------- 1 root root 7, 6 Jan 1 00:47 loop6
brw------- 1 root root 7, 5 Jan 1 00:47 loop5
brw------- 1 root root 7, 4 Jan 1 00:47 loop4
brw------- 1 root root 7, 3 Jan 1 00:47 loop3
brw------- 1 root root 7, 2 Jan 1 00:47 loop2
brw------- 1 root root 7, 1 Jan 1 00:47 loop1
brw------- 1 root root 7, 0 Jan 1 00:47 loop0
brw------- 1 root root 253, 1 Jan 1 00:47 cyasblkdevblk0p1
brw------- 1 root root 253, 0 Jan 1 00:47 cyasblkdevblk0
drwxr-xr-x 9 root root 3260 Jan 1 00:47 ../
drwxr-xr-x 3 root root 880 Jan 1 00:47 ./

uname -a
Linux localhost 3.0.15-SPH-D710.FC06-CL210242 #3 SMP PREEMPT Mon Mar 5 17:04:41 KST 2012 armv7l GNU/Linux

cat /proc/partitions
major minor #blocks name

179 0 15388672 mmcblk0
179 1 20480 mmcblk0p1
179 2 1280 mmcblk0p2
179 3 1280 mmcblk0p3
179 4 8192 mmcblk0p4
179 5 8192 mmcblk0p5
179 6 8192 mmcblk0p6
179 7 307200 mmcblk0p7
259 0 16384 mmcblk0p8
259 1 524288 mmcblk0p9
259 2 2097152 mmcblk0p10
259 3 12066816 mmcblk0p11
259 4 319488 mmcblk0p12
179 16 512 mmcblk0boot1
179 8 512 mmcblk0boot0
253 0 31166976 cyasblkdevblk0
253 1 31162880 cyasblkdevblk0p1

Thanks for any ideas out there...

EDIT: One last thing - when trying to cwm-flash the CM9 rom now, it hangs at "Installing update..."

---------- Post added at 09:33 AM ---------- Previous post was at 08:44 AM ----------

An update: I went through Rogue cwm and chose Mounts & Storage->Mount /data and it gave me an error, then I chose Format /data. It hung, adb died, but when I rebooted, I could mount /data (from adb shell) and touch a file there. It persisted after reboot. So I can write to /data. Sometimes. So again, this seems like a different situation than others have seen - though I am still dead in the water at my knowledge level.