[Samsung Galaxy S8 Questions and Answers] Funkmonkey:
I think we might be looking at different issues.

This is to fix a semi bricked phone that has locked up its bootloader. In the past to resurrect a samsung all you had to do was flash twrp and your new rom but since Oreo some funkiness has been added to the system which only lets you flash a stock rom, (i.e. restoring a phone to factory settings and software) via ODIN/HEIMDALL then it locks up the bootloader for a week so you CANNOT flash anything into the phone that modifies the bootloader (i.e. TWRP OR *any* rom) until its timer runs out. This is most likely an anti theft feature esp with samsung and google pay use as it means there is no way to easily break into a stolen phone and use it as normal, and reflashing breaks all of the security features of the phone (e-fuse) - no knox no samsung or google pay no samsung pass as your device is insecure and could spoof false banking details etc.

The rom i linked to is important as it is a new AUSTRALIAN unbranded STOCK rom, that for some reason you can flash OVER a locked bootloader, meaning you can resurrect (australian at the very least) SN-G950F phones (exynos)

If you already have a working phone and can get to your developer settings then most of this thread is irrelevant to you.

Now - OEM unlock - You just bought a brand new galaxy from samsung (or youre me and you bought a MINT second hand one from cash converters for $700 less) - your phone is factory standard and schmicky. THE BOOTLOADER IS LOCKED. THE RMM STATE SHOULD NOT be triggered. If right now you went to flash something it would fail.

So you go to about phone - software information and you tap 'build number' seven times to unlock developer mode. Hit back twice and developer mode will be at the bottom of settings.

Click into this and you should see without swiping down 'OEM UNLOCK' - If you enable this, you can then reboot straight into download mode (power vol down and bixby) and flash twrp or whatever rom.

If you dont see this option, you either have a snapdragon model (youre **** outta luck permanently) or RMM is PRENORMAL and you either have to try the unlock trick(s) or leave your phone SWITCHED ON for 1 week and it will unlock itself.

The biggest issue at the moment is that i keep breaking something after i attempt to root so not sure whats happening there so use major caution.

Now as i said the trick posted above to unlock without having to wait a week (which i think youre asking about) im now not sure how it works because i cant get it to work any more.

Automatic time and date off, set date back 8 days, reset the phone. Do this a couple of times, then turn on automatic date and time again. HERE THERE BE ISSUES. When i first did it - i switch off time and date and change then reset, when the phone came on, auto date and time was on again. Turn off, change date, reset. Again, its back on. Turn off, change date, reset. Its back on. I give up and leave it, and notice later the option was available, so it worked. I broke the phone, reflashed again, did the trick in ONE reboot. Fcked something again, reflashed, now auto time and date stays off and the trick wont work so i cant help you with that until someone comes up with more info im sorry! Its a bit zarbis.

Im not going too nuts trying to fix it as i now have a fully working stock backup phone that sits on DeX plugged into my bedroom tv full time and im not into custom roms, root keeps breaking the phone, and ive sonce replaced it with a mint S8+ that im not even THINKING about considering rooting until its replaced maybe next year. Its not as easy to get around anymore and thankfully a) picasa and hangouts are no longer stock apps and can be banished and b) you can now disable all the other built in apps natively so its now a lot more bearable with a totally stock phone.