Boot Problem after Successful TWRP flash

[rebgershon]

Hi,
I'm sure someone else will have had my problem but I can't seem to find a straight forward solution.

I am wanting to upgrade my Samsung S7 Edge, SM-G935F Exynos, to the latest Lineage OS with Android 10 as Samsung are no longer supporting my phone. The phone is unlocked as supplied from Samsung.

I downloaded Odin v3.14 and successfully flashed TWRP 3.4.0.0 hero.2lte.img.tar. I activated Developer Options and OEM unlock before flashing.

I can enter TWRP but am unsure what I do regarding the Unmodified System Partition options on the 1st TWRP screen so I hit 'Keep Read Only' and then 'Reboot' only to find that the phone attempts to restart, I see the Samsung Galaxy S7 Edge splash screen which then goes off and restarts again repeatedly, so I can't check if all my data etc. is ok on the phone. I did back up Whatsapp and made s Smart Switch backup too but forgot to do Samsung & Google account backups before the flashing.

I'm assuming I've missed something out in the flashing procedure but am not sure of exactly what. I have previously flashed and upgraded Galaxy S3, S3 Mini & a Tab2 10.1 using earlier TWRP versions so it's not that I'm a total beginner. I also tried to do a rom backup via TWRP but that failed and also a wipe Dalvik cache but that also failed.

Please advise:
1. what I've done wrong if anything?
2. Best way to restore the phone without losing existing data if possible perhaps with stock rom flashing? I could try the Smart Switch Emergency Software recovery & Initialisation but I understand that resets the phone to Factory settings loosing all data.
3. Procedure to flash Lineage rom that's 'idiot proofed'?

Thanks in advance.

 

[shah22]

Hi,
I'm sure someone else will have had my problem but I can't seem to find a straight forward solution.

I am wanting to upgrade my Samsung S7 Edge, SM-G935F Exynos, to the latest Lineage OS with Android 10 as Samsung are no longer supporting my phone. The phone is unlocked as supplied from Samsung.

I downloaded Odin v3.14 and successfully flashed TWRP 3.4.0.0 hero.2lte.img.tar. I activated Developer Options and OEM unlock before flashing.

I can enter TWRP but am unsure what I do regarding the Unmodified System Partition options on the 1st TWRP screen so I hit 'Keep Read Only' and then 'Reboot' only to find that the phone attempts to restart, I see the Samsung Galaxy S7 Edge splash screen which then goes off and restarts again repeatedly, so I can't check if all my data etc. is ok on the phone. I did back up Whatsapp and made s Smart Switch backup too but forgot to do Samsung & Google account backups before the flashing.

I'm assuming I've missed something out in the flashing procedure but am not sure of exactly what. I have previously flashed and upgraded Galaxy S3, S3 Mini & a Tab2 10.1 using earlier TWRP versions so it's not that I'm a total beginner. I also tried to do a rom backup via TWRP but that failed and also a wipe Dalvik cache but that also failed.

Please advise:
1. what I've done wrong if anything?
2. Best way to restore the phone without losing existing data if possible perhaps with stock rom flashing? I could try the Smart Switch Emergency Software recovery & Initialisation but I understand that resets the phone to Factory settings loosing all data.
3. Procedure to flash Lineage rom that's 'idiot proofed'?

Thanks in advance.

1] You didn't formatted /data and/or flashed magisk or supersu after booting into twrp first time.
Note that you need to format /data under wipe in twrp and type yes and then again reboot in twrp. This is necessary step to disable encryption. And after that flash magisk without any reboot or flash your required rom by following your respective rom thread.

Please note that keeping system read only will cause you to flash in systemless root mode like magisk or super su in systemless mode. There is no difference between normal root mode and systemless root mode except that you will need to allow system modifications in twrp in normal root which will in turn trigger dm verity check and you will need to flash no verity zip to make phone bootable when system modification method (normal root) is selected. Plus system modification will cause certain apps to detect root easily plus increasing complications like I said above. So just keep read only and flash magisk and you will get root in systemless mode without any cons !

Here, you said you're getting a verification screen after rebooting twrp..
This can be caused either by.

1. Not formatting /data after booting twrp for first time
2. Not flashing magisk after formatting /data
3. Enabling system modifications and not flashing no verity zips/magisk
4. Oem unlock is not enabled..

2] You cannot restore data if you didn't back it up before messing with it, or you made a titanium backup/twrp backup.
Smart switch cannot flash phone anymore ..

Yes, flashing stock firmware using home_csc in odin, will not delete data and may restore your phone, but no guarantee that it will work, you can try though. Thats why its strictly advised to do backup before messing your phone in anyway..

3. Pls refer or ask in your respective rom thread.

Sent from my hero2lte using XDA Labs

 

[rebgershon]

1] You didn't formatted /data and/or flashed magisk or supersu after booting into twrp first time.
Note that you need to format /data under wipe in twrp and type yes and then again reboot in twrp. This is necessary step to disable encryption. And after that flash magisk without any reboot or flash your required rom by following your respective rom thread.

Please note that keeping system read only will cause you to flash in systemless root mode like magisk or super su in systemless mode. There is no difference between normal root mode and systemless root mode except that you will need to allow system modifications in twrp in normal root which will in turn trigger dm verity check and you will need to flash no verity zip to make phone bootable when system modification method (normal root) is selected. Plus system modification will cause certain apps to detect root easily plus increasing complications like I said above. So just keep read only and flash magisk and you will get root in systemless mode without any cons !

Here, you said you're getting a verification screen after rebooting twrp..
This can be caused either by.

1. Not formatting /data after booting twrp for first time
2. Not flashing magisk after formatting /data
3. Enabling system modifications and not flashing no verity zips/magisk
4. Oem unlock is not enabled..

2] You cannot restore data if you didn't back it up before messing with it, or you made a titanium backup/twrp backup.
Smart switch cannot flash phone anymore ..

Yes, flashing stock firmware using home_csc in odin, will not delete data and may restore your phone, but no guarantee that it will work, you can try though. Thats why its strictly advised to do backup before messing your phone in anyway..

3. Pls refer or ask in your respective rom thread.

Thanks for your reply Shah though I'm still a bit confused by it.
UnIock OEM was enabled as was USB debugging.
Fortunately, I was able to reflash the stock rom and phone is working again but what sort of backup are you indicating in part 2. above), NAND, Smartswitch or just back up to google, Samsung & Whatsapp accounts?
In 1). of your reply you say 'You didn't formatted /data and/or flashed magisk or supersu after booting into twrp first time.
Note that you need to format /data under wipe in twrp and type yes and then again reboot in twrp. This is necessary step to disable encryption. And after that flash magisk without any reboot or flash your required rom by following your respective rom thread.'
I thought that if I do format /data my data would be lost and I want to make a NAND backup of the existing rom and data before flashing/modifying but if that doesn't loose the data, I assume then the steps are as follows:
1. Flash TWRP with Odin
2. Boot into Recovery-TWRP
3. Tap on the Read Only button on the 1st TWRP screen
4. Format /data under wipe in TWRP and tap yes and then reboot in TWRP. - Do you mean reboot the phone into TWRP of just go back into the TWRP main menu & when do I make the NAND backup?
5. Flash magisk or supersu from SD card no reboot
6. Flash Lineage OS rom from SD card.
7. Reboot.

Please correct any errors above as I've now tried 3 times since my original post without success but always managed to reflash the stock rom to get me going again.

 

[shah22]

Thanks for your reply Shah though I'm still a bit confused by it.

Thats why you read forums again and again and unless you are sure and know what you're doing, don't proceed with these things and read again.

UnIock OEM was enabled as was USB debugging.
Fortunately, I was able to reflash the stock rom and phone is working again but what sort of backup are you indicating in part 2. above), NAND, Smartswitch or just back up to google, Samsung & Whatsapp accounts?

Upto you which backup you prefer, saving data on separate storage is the main goal as rooting and flashing custom rom would erase all your data from phone.

I thought that if I do format /data my data would be lost and I want to make a NAND backup of the existing rom and data before flashing/modifying but if that doesn't loose the data, I assume then the steps are as follows

What you mean exactly ? What doesn't loose the data ? Flashing custom rom first time/rooting always erases your data and yes you need to backup before flashing/modifying.

1. Flash TWRP with Odin
2. Boot into Recovery-TWRP
3. Tap on the Read Only button on the 1st TWRP screen
4. Format /data under wipe in TWRP and tap yes and then reboot in TWRP. - Do you mean reboot the phone into TWRP of just go back into the TWRP main menu & when do I make the NAND backup?
5. Flash magisk or supersu from SD card no reboot
6. Flash Lineage OS rom from SD card.
7. Reboot.

In step 4. Reboot again in twrp after formatting /data.

When do you make nand backup?? Lol, at this point your phone would have nothing to backup, you should have made a backup the first time you tried modifying your phone. Because flashing stock rom like you said you did many times, already formats the phone.

If you mean you want to backup your phone again, then you can't backup in twrp in this stage. Backup before flashing twrp through any means.

Step 5 is correct, I don't know about step 6. I never flashed lineage and have no experience about it. Pls refer lineage's respective rom thread for exact steps. Good luck

Sent from my hero2lte using XDA Labs

 

[rebgershon]

Thats why you read forums again and again and unless you are sure and know what you're doing, don't proceed with these things and read again.



Upto you which backup you prefer, saving data on separate storage is the main goal as rooting and flashing custom rom would erase all your data from phone.



What you mean exactly ? What doesn't loose the data ? Flashing custom rom first time/rooting always erases your data and yes you need to backup before flashing/modifying.



In step 4. Reboot again in twrp after formatting /data.

When do you make nand backup?? Lol, at this point your phone would have nothing to backup, you should have made a backup the first time you tried modifying your phone. Because flashing stock rom like you said you did many times, already formats the phone.

If you mean you want to backup your phone again, then you can't backup in twrp in this stage. Backup before flashing twrp through any means.

Step 5 is correct, I don't know about step 6. I never flashed lineage and have no experience about it. Pls refer lineage's respective rom thread for exact steps. Good luck

Sent from my hero2lte using XDA Labs

Thanks again Shah for your reply/help.

I followed the instructions and got the lineage rom installed and Gapps but I don't think Gapps installed properly as I wasn't able to restore any of the saved data from my google account and it wouldn't allow me to add any other accounts except email so for now I've restored the stock rom and my data.

Is there another Android 10 rom you can recommend besides lineage that will have a similar appearance to Samsung?

 

[shah22]

Thanks again Shah for your reply/help.



I followed the instructions and got the lineage rom installed and Gapps but I don't think Gapps installed properly as I wasn't able to restore any of the saved data from my google account and it wouldn't allow me to add any other accounts except email so for now I've restored the stock rom and my data.



Is there another Android 10 rom you can recommend besides lineage that will have a similar appearance to Samsung?

I don't recommend any rom except a stock rooted debloated one.. (like Alexndr's devbase)
Reason : because full custom roms have a high chance to mess up your phone's efs and permanent soft brick issues.

But, I'm in love with infinity wallpapers, dark mode and android 10 in general like all others these days.. so if you really want samsung android 10 for S7 edge, then Floyd V4 is your best bet.. see on rom and software developer section of s7 edge to find floyd v4. Its a s9 android 10 one ui 2 port...

Personally, I'm using latest alexndr's devbase rom. Because I'm still paranoid about fully custom or ported roms

Alexndr's devbase is a full stock oreo - debloated rom. Which has option to root during flashing in twrp too. Its perfect for my needs.

But maybe soon, I will change to Floyd v4 to experience the future.. who knows

Sent from my Legendary Hero2LTE using Tapatalk

 

[rebgershon]

I don't recommend any rom except a stock rooted debloated one.. (like Alexndr's devbase)
Reason : because full custom roms have a high chance to mess up your phone's efs and permanent soft brick issues.

But, I'm in love with infinity wallpapers, dark mode and android 10 in general like all others these days.. so if you really want samsung android 10 for S7 edge, then Floyd V4 is your best bet.. see on rom and software developer section of s7 edge to find floyd v4. Its a s9 android 10 one ui 2 port...

Personally, I'm using latest alexndr's devbase rom. Because I'm still paranoid about fully custom or ported roms

Alexndr's devbase is a full stock oreo - debloated rom. Which has option to root during flashing in twrp too. Its perfect for my needs.

But maybe soon, I will change to Floyd v4 to experience the future.. who knows

Shah,

Many thanks for the recommendation of the FloydQ rom.

I installed it yesterday after making all backups inc. Smartswitch.
Very easy to install both from flashing and Aroma installation viewpoints. Ran 1st time without a glitch and phone now thinks its an S9+ running Android 10 a la Samsung. I even managed to transfer my Smartswitch backup to my wife's old S7 Edge and then used Smartswitch to transfer from that phone to the 'S9+'.

Only glitch was logging into my Samsung account but sorted that as well so all in all very happy so far.:good: