Windows 10 Black Screen With Flashing Underscore

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Jkoukal

Commendable
Jan 13, 2017
16
0
1,510
Hi, so I was going to let my computer do a routine update that required restart overnight and by the time I go to check on it in the morning I'm greeted with a black screen that has a flashing underscore in the upper left corner of the screen that's about 2 lines down. It will load the bios splash art and let me go into the bios (in my case I have an MSI motherboard). And I have tried putting a windows installation media (USB) and loading that and choosing repair instead of install and I don't get the option to boot into safe mode (tried f8 and tried going through the advanced settings but the startup options isn't even an option). Tried startup repair but it said that it couldn't fix my problem, then tried to restore to a previous build and it wouldn't let me. I was able to navigate to the command prompt and notepad to see if my hard drive was picked up and it was, looked through and all my documents appeared to be there. I was able to pull what I needed/wanted on a small USB stick but I would like to not have to wipe my HD clean and start over. Any help is much appreciated. This is the end of 2 consecutive days of looking stuff up and a worthless phone call with windows support center, so any ideas are much appreciated. Thanks.
 
Solution
NTFS = New Technology File System. Its what every version of windows used since XP - http://www.howtogeek.com/235596/whats-the-difference-between-fat32-exfat-and-ntfs/

Since you already have win 8 on PC it has GPT now, that is clear when error mentioned the EFI partition
File:\EFI\Microsoft\Boot\BCD
error code: 0xc000000f

As far as I know, all motherboards that have UEFI also support Legacy mainly as it lets them sell more of them, and because UEFI is backwards compatible.

Repair MBR - you are right but its like why people still say BIOS, MBR & BIOS have been used for last 26 years, it will take a while for people to change. Instead, rebuild bcd & rebuild MBR on Win 10 mean the same things, or should I say, the solution to...

Colif

Win 11 Master
Moderator
Yes, i have all my steam games and documents, music, pictures, and other things I don't want to lose on 2tb drive (its also backed up on cloud servers and USB sticks) and SSD only has windows and any programs I would have to reinstall anyway. It makes recovery much faster after a fresh install, I always have 2 drives in case 1 dies, I don't lose everything
 

Jkoukal

Commendable
Jan 13, 2017
16
0
1,510


what kinda programs would you have to reinstall in that case? Like what kinda programs would have to be dependent on windows to where you would need to reinstall them? Like if I had OBS or Steam I would be alright right?
 

Colif

Win 11 Master
Moderator
With Steam, I put all my libraries on my 2tb drive but the actual steam client goes on C drive. Steam libraries can be reused on another install, just need to point the client at the library and it will find all the games, saves downloading them all.

Most program files go on C, as the way win 10 knows where all the files are for a program is via a registry entry that is created when they are installed. So the majority of programs need to be reinstalled just so win 10 knows they are there. I don't know about OBS but i would assume it needs to be installed again. even programs installed on another drive would need to be reinstalled after a clean install/reset, so its why i just put everything on C,

WOW is one of few other games you can use without reinstalling and all you need do is point a shortcut at the loader and it will work.

oh, i also move my onedrive folder as mine is 36gb in size and I don't need it sitting on my C drive. I think next time i clean install i might wipe the hdd at same time... its getting messy.
 

Jkoukal

Commendable
Jan 13, 2017
16
0
1,510
Is there a way that I could figure out all the programs I have on the old HDD (Current broken one) I have? (guessing maybe the "programs" folder......) And so basically what your saying is as far as the program goes it needs to be on the same drive just so windows doesn't lose its mind trying to find it, but all the data of those apps (like games in steams case) could be on the other HDD? Btw thanks for being so helpful most activity I've gotten on several forums I posted my problem to.
 

Colif

Win 11 Master
Moderator
You could navigate to the E:/Program files & E: /Program files (86) folders in command prompt and have a look though if those folders anything like mine the lists will be long

you could use the ubuntu disc I linked to above and use it to look in the programs folder of C drive. it runs off the disc I believe so you can use it to look

Any data could be put on hdd, but all the actual program files need to be with the program itself
 

Colif

Win 11 Master
Moderator


I missed this bit

NTFC?? all I can find is a foorball club in UK, I doubt that is right :)

The other three are related
UEFI = Unified Extensible Firmware Interface - Its what you call the BIOS but its the new version meant to replace the BIOS... people are just slow to stop calling it the BIOS but generally now, any PC made in last 6 years has a UEFI
GPT = GUID Partition Table - this is the disc format windows 10 and windows 8 use. It replaces the old partition scheme that every version of Windows used before them. The old scheme has limits that were becoming a limit - it could only access 2 tb max, so if you had a 3tb drive, the old scheme couldn't see the extra 1tb. GPT drives can be so big the size limit won't be a problem for a long time.

before you ask... GUID = Global Unique ID - every single boot device on earth has a unique number so the PC knows exactly which device you mean... you don't need to worry about this, PC does it all behind scenes.
Before GUID the hdd you booted off had to be in a particular order in the boot order. Now the Windows Boot Manager has a list of all the GUIDs and just finds the drive it needs, regardless of drive order.

UEFI + GPT replace Legacy BIOS + MBR. They match each other and while you can boot a MBR system using UEFI, you cannot boot a GPT disk using Legacy

http://www.howtogeek.com/193669/whats-the-difference-between-gpt-and-mbr-when-partitioning-a-drive/

EFI is a partition on the GPT drive that holds the boot files for windows 10
 

Jkoukal

Commendable
Jan 13, 2017
16
0
1,510
Haha I meant NTFS, like when you do the check disk and it says it under Fs. And so theoretically if I were to wipe and clean install windows my computer wouldn't have a MBR it would change to the GPT. (And since in my BIOS (UEFI) it says UEFI + Legacy mode that my motherboard supports both?) and if so why would I have the option to repair my MBR if it technically doesn't exist? And also like a GUID could be like the MAC address that a network uses to identify which device is what? and so does the bcd (boot config data if I'm not mistaken) still apply to the GPT? Sorry I'm hammering you with questions..-_-
 

Colif

Win 11 Master
Moderator
NTFS = New Technology File System. Its what every version of windows used since XP - http://www.howtogeek.com/235596/whats-the-difference-between-fat32-exfat-and-ntfs/

Since you already have win 8 on PC it has GPT now, that is clear when error mentioned the EFI partition
File:\EFI\Microsoft\Boot\BCD
error code: 0xc000000f

As far as I know, all motherboards that have UEFI also support Legacy mainly as it lets them sell more of them, and because UEFI is backwards compatible.

Repair MBR - you are right but its like why people still say BIOS, MBR & BIOS have been used for last 26 years, it will take a while for people to change. Instead, rebuild bcd & rebuild MBR on Win 10 mean the same things, or should I say, the solution to both is the same.

GUID is probably like a MAC address (networking isn't one of my strong points). MBR only allowed you to boot from a limited range of device types, GUID lets you boot from devices that may not exist yet, as well as the usual network drives, It recognises the internet of things, so it could boot up off your fridge or remote control for house...

your error i quoted above also answers the bcd question. it exists in both MBR & GPT, been around since Vista - https://en.wikipedia.org/wiki/Windows_Vista_startup_process#Boot_Configuration_Data
 
Solution
Apr 28, 2019
1
0
10
This is what i found out for anyone who is using a server or server motherboard,
If you have a usb or other storage device inserted, when you boot up your device it will automatically attempt to boot from the device instead. so make shure you dont have a usb or other storage device inserted.
 
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