Galaxy S7, problems booting

[Android Central Question]

I will try to be as step-by-step concise as possible.

Samsung Galaxy S7...

Initial problem was "green light - black screen" issue.

I did a lot of web search; went through MANY options of different button combination recovery boots, which brought me to the famous "no command" screen many times, and many unsuccessful reboot attempts.

Sometimes, the dead robot - exclamation mark - "no command" screen would lead me into the options screen. I cannot lose my data, so I did not choose factory reset. Instead I chose 'reboot'.

Selecting 'reboot' leads to the phone continuously restarting the initial Samsung Galaxy S7 screen, but would not lead to the animated "SAMSUNG" logo, it would just restart again to the initial Samsung Galaxy S7 screen.

In the middle of this continuous restarting, I disconnected the battery cable clip (with charger plugged in.)

This caused the phone to restart with the lightning bolt charge indicator on screen, at which point indicated I had 82% charge.

Now the phone is off, and is charging with the red light on, as if everything was normal.

IMPORTANT NOTE, I have reached this stage before, and when the green light indicating full charge came on, I reconnected the battery cable clip, and pushed the power button to turn on as I normally would. The phone started with the initial screen, and then DID proceed to the animated "SAMSUNG" logo, and one time even got me to my pin entry, but then died and went back to not restarted properly.

FINALLY, MY QUESTION, now that the phone is in a "normal" state of charging, what should I do first when the green light comes on to indicate full charge?

Connect battery cable clip again? Try to Power button Volume Down button for safe mode? I seem to be close to a successful restart again, and am unsure of the best procedure.

Also, could simply replacing the battery be the solution?

I cannot express enough my gratitude to any advice anyone out there can provide. Thank you immensely!!

 

[mustang7757]

Can you get into download mode or recovery?

I'll leave a Link to register so you can communicate here as a guest account you can only post questions but can't reply.
https://forums.androidcentral.com/showthread.php?t=409154

 

[smvim]

So there's the normal mode you would typically boot up and use your S7, which unfortunately isn't working in your case, and three alternative modes
-- Recovery Mode is a lower level maintenance mode where you simultaneously press and hold the Power, the Home, and the Volume Up buttons.
https://www.hardreset.info/devices/samsung/samsung-g930f-galaxy-s7/recovery-mode/
Note that Recovery is a text-only mode so you need to use the indicated buttons to navigate through the various menu options. It's also really easy to wipe your phone or soft brick it so be very careful and only use this when you need to, not when you're just experimenting and guessing. It does sound like that's what you've been doing so just be cognizant of any adverse after-effects.
-- Download Mode is used to install firmware (i.e. a custom Recovery like TWRP, or a stock or custom ROM). To get into it, you need to use the Power, the Home, and the Volume Down buttons.
https://www.hardreset.info/devices/samsung/samsung-g930f-galaxy-s7/download-mode/
-- Safe Mode is a way of running your Android device with only the base Android operating system. No third-party apps or services get loaded into memory during start up, just the OS. But you do need to have a working Android OS to even reboot into Safe Mode, which is apparently the problem with your S7 at this point -- you cannot boot up into Safe Mode when there's no functional OS to actually start up into.
https://www.hardreset.info/devices/samsung/samsung-g930f-galaxy-s7/safe-mode/
So be careful booting up your phone into its Recovery and/or Download modes, they both have specific purposes.
The internal storage of your S7 is divided up into several partitions, most are dedicated to the Android operating system, one (the biggest) is set aside as the user's data partition. Your data resides in that user data partition and you, the user, has full control over everything in that partition. All those other partitions however have system-level permissions so you don't have any access to them, or at least very little. Going by your posting, it's hard to determine if there's something like a hardware error (the internal storage chip has failed) or if it's just a matter of the installed Android OS became corrupted preventing your phone from booting up normally (a more common occurrence than a hardware failure). If it is hardware, that's typically a service shop repair. If it's just the Android OS, that's just a matter of flashing a new stock ROM. With Samsung phones, there's a good chance you'll be able to flash a stock ROM and leave the data partition as is. But don't get your hopes up too much. Playing around in the Recovery Mode isn't advisable, and there could be some other problem where your data was wiped or corrupted.
Anyway, try the easiest thing to try is install Samsung's Smart Switch utility:
https://forums.androidcentral.com/e...%2Fowners%2Fapp%2Fsmart-switch&token=qZmsmram
Smart Switch is Samsung's multi-function utility which includes a update/repair function. It's probably not going to help you in this matter but worth trying anyway. (... and it installs the latest Samsung driver if you're doing this on a Windows PC, which is a necessary task for the following).
So if that works out, ignore this next suggestion.
-- In order to flash a new, stock ROM on your S7, you need a) a valid, appropriate stock ROM and b) a utility to do the flashing process. Flashing a ROM (a.k.a. firmware) is essentially similar to using a Restore disc/media to reinstall the clean Windows OS on a PC.
Go here and be sure to select the appropriate ROM that exactly matches your S7. Do not substitute or mix-and-match. ROMs are not interchangeable, they are very model specific. So choose the one the exactly matches your S7 model, your country, and your carrier.
https://www.sammobile.com/firmwares/search/galaxy s7/
In the download page of your chosen ROM there will be basic instructions to do the flashing process. Follow them closely. Really. Be sure that the 'Re-Partition' option is not selected. Double-check it isn't checked. Wiping the partition table will definitely remove your data. Using the Odin utility you'll just be reloading the Android OS into those system partitions, the user data partition is left as is. But again, do not select Re-Partition.
Odin is a Windows utility so if you don't have access to a Windows PC, use Heimdall. It's an Open Source equivalent to Odin that's available for Linux, Mac, and Windows. It is not an exact duplicate, so just be flexible as it's functionally the same as Odin but some of its menus and such do vary.
https://glassechidna.com.au/heimdall/
Keep in mind that flashing the ROM might not fix your problem. It installs a clean, working Android OS but if your problem is due to some other issue than you're probably going to need to take your phone to a service center.
Oh, if this does fix your problem, use Smart Switch to do regular backups of your phone. It also includes a handy backup/restore function. You really need to have a backup solution implemented.

 

[jhdesigns]

Done. Thanks Mustang!

 

[jhdesigns]

smvim, huge thanks for the in depth reply! I will work through all your info. Thanks!

 

[mustang7757]

Done. Thanks Mustang!

Hi, welcome to AC!

If you going flash , recommend download frija firmware tool to download your firmware and latest Odin from XDA website onto your PC .

If you need additional steps I can provide those as well