[Galaxy S 4 Q&A, Help & Troubleshooting] voxel.xyz:
SOLVED!!!!!

After nobody answered if I could use again "mobile Odin" to flash once more and try to fix my wifi not working I opened mobile odin and it gave me a warning about my version and having a wrong bootloader as a possibility of soft bricking my phone so I decided to stay away of mobile Odin this time.

I used desktop Odin (at work since my pc broke) and exactly the same firmware file downloaded from sammobile (but re-downloaded it just in case) and had to flash twice, the first time it went through the whole process ok right until the end where it showed the FAIL message.

I didn't know if I should turn off the phone stuck in download mode and with the process bar at 100 % or retry flashing without turning it off. So I decided not to turn it off (afraid it would get soft bricked or something). I closed mobile Odin but left phone On with download mode screen active and opened mobile Odin again got the "added"message and the blue color showing it was properly connected to the phone and started flashing process again....

I started getting red error messages saying the progress bar display was wrong (and it wasn't updating/kept stuck in the previous 100%) but after it finished it was flashed and everything was ok. WIFI WORKED!!!!!!

Now the weird part.....in case this happens /helps someone else:

- My phone DID NOT get wiped. My launcher and my apps stayed intact (I thought flashing even the same firmware always wiped data, I'm I wrong???)

- All my root apps (root explorer, titanium backup, so on and so forth) where there and working fine. One root checker stated I was rooted and another one stated I wasn't but even my launcher (nova) was working just as if I never flashed the phone.

- Since I was unsure of my "root" state and I did not have "supersu" app in my apps drawer I tried installing it via playstore but It always gave an error message (the application could not be installed in the default location)

- I rooted again just in case and the root process finished without errors but still I had no "supersu" app and one root checker said I was rooted and the other I wasn't. Tried installing "supersu" from the playstore but same error and could not get installed.

- I searched here and in other forums for similar problems/solutions but nothing worked until I tried several things that fixed the problem. Not really sure which fixed it so I will write them down in the order I did them:

1. Opened folder mount which I already had installed and it gave me an error and asked me to try the fix which I did.

2. Opened linked2sd which I already had installed also previous to the firmware flash. It gave me an error and asked me which was the partition to use (as when I first installed it) in my case it was ext4. And it seemed to start working as it normally does. No further error when reopening it.

3. Rebooted the phone and tried entering recovery mode to wipe cache etc but It never entered recovery mode. I get the message about going into recovery mode (top left corner small red letters) But right after that it reboots and I get the samsung logo and my home screen.

4. Tried reinstalling supersu again and no success. (By the way before I did all this steps I tried rooting again but got to the same point. No supersu on my apps drawer)

5. Downloaded BusyBox install (opened it but did not use it in any way, maybe something in the installation fixed my problem)

6. Opened mobile Odin just for curiosity sake and it opened fine and asked for downloading of the extra stuff as when I installed it the first time. After that I closed it

7. Rebooted normally (no recovery mode since I'm stuck without it)

8. Tried installing "supersu" and NOW it worked!!!

9. Checked in both root checker apps and both confirm I'm rooted and supersu started asking for granting permissions to apps again as it normally does!

10. Everytime I attempted flash, root, and even after some reboots I took the battery off (since I read in several threads it helped/was mandatory)

Conclusion now my WIFI problem is fixed, my root problem (that appeared doing the reflash for fixing my wifi problem) is also fixed. The only thing I could not fix is not being able to get into recovery mode.

Does anyone know a solution for recovering the ability to get into recovery mode????

Thanks to Joku for lighting me into re flashing once and again until my wifi was fixed!