[GUIDE] Android deep clean-up / wipe
Now with the release of many JB leaks for our Galaxy Note, more and more people are starting to flash custom ROMs into their devices. However, many don't do a proper clean-up / wipe of their devices before doing so, complaining about supposed "bugs" that in fact are not real bugs, but just incompatibilities with previous app data and config left from the previous ROM or improperly restored from backups (TB etc.).
So, after facing that myself with the first ROMs I flashed, reading a lot of tips from the senior members, and experimenting different approaches, I came up with a method that I always follow before flashing a new ROM, which gives me less or no issues at all.
you minimize the chance of having issues when flashing a new ROM.
you have to manually reinstall your apps (can be somewhat automated from Google Play) and reconfigure everything.
I'm assuming you have CWM installed and know how to use it, and are not a complete noob. If you don't, search the forums and read the guides. Read this guide fully and make sure you understand everything before proceeding.
IMPORTANT: ONLY wipe your device if you have a SAFE (BRICK-FREE) KERNEL. Check your kernel and search the forums. Don't proceed if you are not sure! I'm not responsible for any bricks, unexpected issues that can happen to you or personal data loss because you forgot to backup that! If you want to stay safe, don't want to experiment with your cell phone, it's critical you have it working everytime, stay with the official Samsung ROMs updates you get OTA and don't proceed with this how-to.
1) Boot into recovery and perform a full backup (a.k.a. nandroid) to your internal or external SD card.
2) Reboot, and create backups of personal data needed from your apps in your internal or external SD card. For instance, I backup data from apps which are not cloud-based; they usually have a "backup" menu for that.
3) Plug your device into your computer, and copy everything you need from your internal and external SD cards (including the backups done in 1) and 2)). Don't forget your pictures and MP3 files.
4) Delete any apps and data from your external SD card. Leave it as clean as possible (it's OK to leave personal data such as MP3s, pictures etc.).
5) Copy the ROM you are about to flash to your EXTERNAL SD Card (don't copy to internal, because we are going to wipe it).
6) Boot into CWM Recovery and do the following wipes:
6.1) Wipe data / factory reset
6.2) Wipe cache partition
6.3) Advanced -> Wipe dalvik cache
6.4) Mounts and Storage -> Format /system
6.5) Mounts and Storage -> Format /preload
6.6) Mounts and Storage -> Format internal SD card (make sure you know if your internal SD card if /emmc or /sdcard; see below!)
7) Install Zip -> Flash ROM from your external SD card.
8) Wipe cache partition again.
9) Advanced -> Wipe dalvik cache again.
11) Don't restore anything from Titanium Backup. Reinstall and reconfigure everything from Google Play. I never tried but I think that if you just restore user apps, it should work. Just never restore system apps and data.
The backups you created in step 2) and copied to your computer in step 3) can be safely restored from within the apps themselves.
Now you may ask why we format the internal SD card. Many apps store their configuration and app data there, so this way we ensure no old data and config are there which may be incompatible with the new ROM. In fact it might not be that important, since it's only related to user apps, but I prefer to clean everything before flashing a new ROM.
How to find if your internal SD card is mounted on /emmc or /sdcard in CWM Recovery:
1) Boot into CWM Recovery.
2) Install Zip -> Choose zip from internal sdcard. In the top you can see where yours is mounted (/emmc or /sdcard).
3) This is the partition you should format in step 6.6. Pay attention to not format the external SD card, because the ROM zip file is there!
If you still have issues after flashing a new ROM, try to reflash it without any wipes (i.e. just do step 7 again).
Hope it can help people with their flashing!