[Samsung Epic 4G Touch] kobridge:
This is the story about what happened to my phone today during the ROM upgrade from FC15 to FC18 and how to get out from Samsung Galaxy S II logo screen (if phone is frozen in there), and finally successfully installed FC18 from previous version. I believe my situation that I've experienced today would be most common situation that many people bricked their phone these days and posted their problems in our Q&A session.

OK. Let get started.

I think I was lucky(?) enough today because I've experienced the same thing that lots of people these days reported the issue happened during flashing their Roms. I gave them lots of advice but couldn't solve the issue directly because there are lots of possibilities. My case would be one of the possibilities but may help lots of people too.

One scenario that your phone could stop during the flashing -> Not consistent flashing.

Sometimes I've used Calk's Rom and some other times I've used one-click odin package to flash the rom, kernel and modem. Most recent my pass was, Calk's FC07 Rooted Stock -> sfhub's one-click Rooted FC15 -> Calk's FC18 Rooted Stock. I think if you are moving between Rogue recovery mode and odin mode, the chances that your phone could be bricked are getting bigger.

Before explaining what I did to successfully install FC15, what I'm writing in here is informational purpose only. If you want to follow the same step, please do it with our own risk.

The steps that I followed:

1. The base Rom was FC15 and it was installed thru one-click odin. I installed this version from Calk's FC07.

2. To install Calk's FC18, I flashed Rogue_ET-Stock-1.1.4 tar file thru mobile odin

3. After the Rogue Kernel installed, during the reboot, I moved to Rogue Recovery by pressing vol up + power

4. From the Rogue recovery, I manually cleaned cache/Dalvik/Battery and ran the Calk's modified format all zip file (I do not want to delete my data and spent lots of time to recover it after the rom installed)

5. Installed Calk's Rooted Stock FC18 Rom - *same recovery session, no error

6. Installed Calk's FC18 modem - *just after rom installed, no error

7. Ran Calk's Bare Rom converter 1.3 - *just after modem installed, no error

8. Reboot

9. Now the phone was stuck at Samsung Galaxy S II first screen forever (feeling like bricked or frozen)

The above steps were the steps showing how my phone was stuck in boot screen.

Now let's move to the next step. The following steps were my trial steps to successfully install FC15 rom.

10. My phone was stuck on boot screen, power button and vol up + power didn't worked. Only showed the battery charging status, not moving to other state.

11. Only the key combination was power + vol down (Download mode) and this means that only odin could work.

12. Plugged usb cable to pc and flashed the previous rom again using one-click odin (FC15-CL256308_ROOTED_NODATA-oc-sfx.exe). Flashing didn't show any error and successfully passed.

13. Phone rebooted (stock recovery) and I was able to see everything again from my phone (apps + data).

14. Flashed Rogue FC07 based recovery at this time using mobile odin (rogue_ET-recovery-1.2.2-FC07-rc0.tar

15. At this time did not stop the phone during the reboot and phone completed rebooting. Updated profile and prl. Rebooted phone and moved to Rogue recovery again (vol up + Power)

16. Clean everything again and ran the Calk's modified format all.

17. Installed FC18 rom only at this time

18. Reboot and phone stopped again at Samsung logo.

Repeating the steps again

19. moved back to the step 10 and proceeded to 11.

20. from step 12, instead of flashing whole build, I only flashed FC07 Kernel only thru the odin v1.8.5 (SPH-D710.FC15_CL256308_KERNEL-sfx.eve)

21. Reboot and system came back!

I think some of you already caught the idea in here.

The following steps are the core steps that I did to get rid of stuck boot screen and successfully flash FC15. Because above steps were trial error, you can just follow the below steps.

Final Steps to successfully flashing FC18 from stuck Boot screen:

The following way is only for the case your phone is stuck during the boot.

1. Install Rogue recovery (current version is now based on FC18). I used Rogue recovery 1.2.2 which is based on FC07 Kernel. Rogue recovery 1.2.2 and 1.2.3 are only for ICS roms, so if your current rom is GB based then you have to use 1.1.4 or 1.1.3.

2. From the recovery, wipe all (if you want to keep previous data, don't wipe the data and that's what I did) or run the Calk's format all or modified format all (same as not deleting data).

3. Install Rom and Modem (your choice which one goes first) without reboot

4. Reboot

5. Again phone is stuck on boot screen

6. go to Download mode by pressing vol down + power key at the same time

7. (requires odin PC version) flash the kernel only. You can use the working previous kernel in here or FC18 kernel if it is available.

For me, while I'm working on this issue, stand alone FC18 kernel was not available. So, I unzipped Calk's zip file, extracted zImage file and used it for odin.

8. Reboot

9. Bingo! No stuck on boot screen. After the reboot, if you used previous kernel, then update the kernel thru mobile odin. Or go back to DL mode and odin the kernel again using most recent one. For me, I usually use the zImage file to update the kernel. Be careful when you use the zImage file because I have some experience that this zImage file size is different when it's extracted from phone and PC. I'm not sure it's caused by corrupted zip file or applications extracting the zip file. The total zip file size was same but extracted zImage file size was different (this also could be a reason why phone is stuck on boot screen) - just my guess.

10. All done! Go to setting and update the profile and prl.

Above is all about my story today. There could be something that I missed or incorrectly described. Please be generous and let me know if you want to fix any information from above.