Cross-flashed LG BP50NB40 (NB52) – UHD not reading, Blu-rays are fine
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Cross-flashed LG BP50NB40 (NB52) – UHD not reading, Blu-rays are fine
I apologize if this isn't in the right spot. I've lurked all over these, but never posted until now.
I recently purchased an LG BP50NB40 (SVC NB52) and cross-flashed it using SDFtool Flasher with the BU40N DE firmware. I ensured the bootloader was checked this last time and verified in LibreDrive that the firmware is patched (microcode access re-enabled) with BD raw data and metadata read enabled.
Drive info shows Firmware version 1.03, MT1959 platform, and Highest AACS version: 66.
All-region DVD support and unrestricted read speed are active.
I’m able to read and rip standard Blu-ray discs just fine with MakeMKV, but UHD discs are not being detected. I suspect this may be due to my firmware version or microcode limitations. Anyone have any ideas? Let me know if you have more questions. Regarding the below, when a UHD is inserted, it just says no disk found. For what it's worth I tried with Atomic Blonde, Doctor Sleep, and Jurassic World.
Drive Information
OS device name: \Device\CdRom0
Current profile: BD-ROM
Manufacturer: HL-DT-ST
Product: BD-RE BP50NB40
Revision: 1.03
Serial number:
Firmware date: 2120-05-07 09:17
Bus encryption flags: 17
Highest AACS version: 70
LibreDrive Information
Status: Enabled
Drive platform: MT1959
Firmware type: Patched (microcode access re-enabled)
Firmware version: 1.03
DVD all regions: Yes
BD raw data read: Yes
BD raw metadata read: Yes
Unrestricted read speed: Yes
I recently purchased an LG BP50NB40 (SVC NB52) and cross-flashed it using SDFtool Flasher with the BU40N DE firmware. I ensured the bootloader was checked this last time and verified in LibreDrive that the firmware is patched (microcode access re-enabled) with BD raw data and metadata read enabled.
Drive info shows Firmware version 1.03, MT1959 platform, and Highest AACS version: 66.
All-region DVD support and unrestricted read speed are active.
I’m able to read and rip standard Blu-ray discs just fine with MakeMKV, but UHD discs are not being detected. I suspect this may be due to my firmware version or microcode limitations. Anyone have any ideas? Let me know if you have more questions. Regarding the below, when a UHD is inserted, it just says no disk found. For what it's worth I tried with Atomic Blonde, Doctor Sleep, and Jurassic World.
Drive Information
OS device name: \Device\CdRom0
Current profile: BD-ROM
Manufacturer: HL-DT-ST
Product: BD-RE BP50NB40
Revision: 1.03
Serial number:
Firmware date: 2120-05-07 09:17
Bus encryption flags: 17
Highest AACS version: 70
LibreDrive Information
Status: Enabled
Drive platform: MT1959
Firmware type: Patched (microcode access re-enabled)
Firmware version: 1.03
DVD all regions: Yes
BD raw data read: Yes
BD raw metadata read: Yes
Unrestricted read speed: Yes
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- Posts: 3939
- Joined: Wed Nov 22, 2017 11:45 pm
Re: Cross-flashed LG BP50NB40 (NB52) – UHD not reading, Blu-rays are fine
If you are on Linux, flash the drive to BU40N 1.00 as 1.03-MK is buggy on Linux.steeledrum wrote: ↑Mon Sep 01, 2025 7:34 pmI apologize if this isn't in the right spot. I've lurked all over these, but never posted until now.
I recently purchased an LG BP50NB40 (SVC NB52) and cross-flashed it using SDFtool Flasher with the BU40N DE firmware. I ensured the bootloader was checked this last time and verified in LibreDrive that the firmware is patched (microcode access re-enabled) with BD raw data and metadata read enabled.
Drive info shows Firmware version 1.03, MT1959 platform, and Highest AACS version: 66.
All-region DVD support and unrestricted read speed are active.
I’m able to read and rip standard Blu-ray discs just fine with MakeMKV, but UHD discs are not being detected. I suspect this may be due to my firmware version or microcode limitations. Anyone have any ideas? Let me know if you have more questions. Regarding the below, when a UHD is inserted, it just says no disk found. For what it's worth I tried with Atomic Blonde, Doctor Sleep, and Jurassic World.
Drive Information
OS device name: \Device\CdRom0
Current profile: BD-ROM
Manufacturer: HL-DT-ST
Product: BD-RE BP50NB40
Revision: 1.03
Serial number:
Firmware date: 2120-05-07 09:17
Bus encryption flags: 17
Highest AACS version: 70
LibreDrive Information
Status: Enabled
Drive platform: MT1959
Firmware type: Patched (microcode access re-enabled)
Firmware version: 1.03
DVD all regions: Yes
BD raw data read: Yes
BD raw metadata read: Yes
Unrestricted read speed: Yes
Cheers
----------------------------------------------------------------------------------------------------------------------------
For UHD enabled drives (AU/NZ/SG + Others) & DIY Single Drive Flasher (WW): https://uhdenableddrives.com

----------------------------------------------------------------------------------------------------------------------------
For UHD enabled drives (AU/NZ/SG + Others) & DIY Single Drive Flasher (WW): https://uhdenableddrives.com
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- Posts: 8
- Joined: Mon Sep 01, 2025 7:30 pm
Re: Cross-flashed LG BP50NB40 (NB52) – UHD not reading, Blu-rays are fine
Thanks for the reply! I'm not on Linux. My current workflow is ripping on my Windows 11 machine, and from there I copy the files over to my Plex server which is on Linux. Eventually, I plan to use only one computer, but as I learn things this is how I'm doing it. It is good to know that the firmware is buggy on Linux. I'll keep that in mind once I move over.MartyMcNuts wrote: ↑Mon Sep 01, 2025 11:05 pmIf you are on Linux, flash the drive to BU40N 1.00 as 1.03-MK is buggy on Linux.steeledrum wrote: ↑Mon Sep 01, 2025 7:34 pmI apologize if this isn't in the right spot. I've lurked all over these, but never posted until now.
I recently purchased an LG BP50NB40 (SVC NB52) and cross-flashed it using SDFtool Flasher with the BU40N DE firmware. I ensured the bootloader was checked this last time and verified in LibreDrive that the firmware is patched (microcode access re-enabled) with BD raw data and metadata read enabled.
Drive info shows Firmware version 1.03, MT1959 platform, and Highest AACS version: 66.
All-region DVD support and unrestricted read speed are active.
I’m able to read and rip standard Blu-ray discs just fine with MakeMKV, but UHD discs are not being detected. I suspect this may be due to my firmware version or microcode limitations. Anyone have any ideas? Let me know if you have more questions. Regarding the below, when a UHD is inserted, it just says no disk found. For what it's worth I tried with Atomic Blonde, Doctor Sleep, and Jurassic World.
Drive Information
OS device name: \Device\CdRom0
Current profile: BD-ROM
Manufacturer: HL-DT-ST
Product: BD-RE BP50NB40
Revision: 1.03
Serial number:
Firmware date: 2120-05-07 09:17
Bus encryption flags: 17
Highest AACS version: 70
LibreDrive Information
Status: Enabled
Drive platform: MT1959
Firmware type: Patched (microcode access re-enabled)
Firmware version: 1.03
DVD all regions: Yes
BD raw data read: Yes
BD raw metadata read: Yes
Unrestricted read speed: Yes
Any other ideas?
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- Posts: 480
- Joined: Fri Sep 06, 2024 4:47 pm
Re: Cross-flashed LG BP50NB40 (NB52) – UHD not reading, Blu-rays are fine
You missed a step when you were flashing the firmware as the drive is still utilising the BP50NB40 firmware. This firmware cannot read UHD discs. For slim/portable drives only the BU40N, BP60NB10 and Buffalo firmware variants can read UHD discs.steeledrum wrote: ↑Mon Sep 01, 2025 7:34 pmI recently purchased an LG BP50NB40 (SVC NB52) and cross-flashed it using SDFtool Flasher with the BU40N DE firmware. I ensured the bootloader was checked this last time and verified in LibreDrive that the firmware is patched (microcode access re-enabled) with BD raw data and metadata read enabled.
Once it is flashed correctly the drive info panel in MakeMKV should list the firmware as BU40N and your drive will read UHD discs.
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Re: Cross-flashed LG BP50NB40 (NB52) – UHD not reading, Blu-rays are fine
Can you elaborate on what I missed? I've attached how it looked when I did the flash.keydb_helper wrote: ↑Tue Sep 02, 2025 12:37 am
You missed a step when you were flashing the firmware as the drive is still utilising the BP50NB40 firmware. This firmware cannot read UHD discs. For slim/portable drives only the BU40N, BP60NB10 and Buffalo firmware variants can read UHD discs.
Once it is flashed correctly the drive info panel in MakeMKV should list the firmware as BU40N and your drive will read UHD discs.
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- Joined: Wed Nov 22, 2017 11:45 pm
Re: Cross-flashed LG BP50NB40 (NB52) – UHD not reading, Blu-rays are fine
Yeah, I missed that too! This model must be cross-flashed to either BU40N or BP60NB10 to enable UHD readability (requiring 2 flashes). You have only completed 1 flash, which is the BP50NB40 1.03-MK firmware. This first flash removes the firmware encryption and does enable libredrive but this firmware is not UHD compatable.steeledrum wrote: ↑Tue Sep 02, 2025 1:02 amCan you elaborate on what I missed? I've attached how it looked when I did the flash.keydb_helper wrote: ↑Tue Sep 02, 2025 12:37 am
You missed a step when you were flashing the firmware as the drive is still utilising the BP50NB40 firmware. This firmware cannot read UHD discs. For slim/portable drives only the BU40N, BP60NB10 and Buffalo firmware variants can read UHD discs.
Once it is flashed correctly the drive info panel in MakeMKV should list the firmware as BU40N and your drive will read UHD discs.
You now need to perform the cross-flash to enable UHD readability. Please go to the SDFtool Flasher thread: viewtopic.php?p=94848#p94848 go to the section: to flash the BP50NB40 SVC:NB52 and follow from step 2. There's even a gif showing the process and there's no need to check the boot loader box at all.
Cheers
----------------------------------------------------------------------------------------------------------------------------
For UHD enabled drives (AU/NZ/SG + Others) & DIY Single Drive Flasher (WW): https://uhdenableddrives.com

----------------------------------------------------------------------------------------------------------------------------
For UHD enabled drives (AU/NZ/SG + Others) & DIY Single Drive Flasher (WW): https://uhdenableddrives.com
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- Joined: Mon Sep 01, 2025 7:30 pm
Re: Cross-flashed LG BP50NB40 (NB52) – UHD not reading, Blu-rays are fine
Thanks! I'll give that shot.MartyMcNuts wrote: ↑Tue Sep 02, 2025 4:10 amYeah, I missed that too! This model must be cross-flashed to either BU40N or BP60NB10 to enable UHD readability (requiring 2 flashes). You have only completed 1 flash, which is the BP50NB40 1.03-MK firmware. This first flash removes the firmware encryption and does enable libredrive but this firmware is not UHD compatable.
You now need to perform the cross-flash to enable UHD readability. Please go to the SDFtool Flasher thread: viewtopic.php?p=94848#p94848 go to the section: to flash the BP50NB40 SVC:NB52 and follow from step 2. There's even a gif showing the process and there's no need to check the boot loader box at all.
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- Joined: Mon Sep 01, 2025 7:30 pm
Re: Cross-flashed LG BP50NB40 (NB52) – UHD not reading, Blu-rays are fine
Marty, I have tried this multiple times to no avail. Now I'm concerned, as I cannot even flash to the 1.0 clean firmware you have linked from that link you sent me. For the life of me, I cannot get this to work. Any other ideas?MartyMcNuts wrote: ↑Tue Sep 02, 2025 4:10 amYeah, I missed that too! This model must be cross-flashed to either BU40N or BP60NB10 to enable UHD readability (requiring 2 flashes). You have only completed 1 flash, which is the BP50NB40 1.03-MK firmware. This first flash removes the firmware encryption and does enable libredrive but this firmware is not UHD compatable.steeledrum wrote: ↑Tue Sep 02, 2025 1:02 amCan you elaborate on what I missed? I've attached how it looked when I did the flash.keydb_helper wrote: ↑Tue Sep 02, 2025 12:37 am
You missed a step when you were flashing the firmware as the drive is still utilising the BP50NB40 firmware. This firmware cannot read UHD discs. For slim/portable drives only the BU40N, BP60NB10 and Buffalo firmware variants can read UHD discs.
Once it is flashed correctly the drive info panel in MakeMKV should list the firmware as BU40N and your drive will read UHD discs.
You now need to perform the cross-flash to enable UHD readability. Please go to the SDFtool Flasher thread: viewtopic.php?p=94848#p94848 go to the section: to flash the BP50NB40 SVC:NB52 and follow from step 2. There's even a gif showing the process and there's no need to check the boot loader box at all.
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- Joined: Wed Nov 22, 2017 11:45 pm
Re: Cross-flashed LG BP50NB40 (NB52) – UHD not reading, Blu-rays are fine
Then you are not following the instructions exactly!! Each file selection window tells you what to select in the title.steeledrum wrote: ↑Tue Oct 07, 2025 2:53 amMarty, I have tried this multiple times to no avail. Now I'm concerned, as I cannot even flash to the 1.0 clean firmware you have linked from that link you sent me. For the life of me, I cannot get this to work. Any other ideas?MartyMcNuts wrote: ↑Tue Sep 02, 2025 4:10 amYeah, I missed that too! This model must be cross-flashed to either BU40N or BP60NB10 to enable UHD readability (requiring 2 flashes). You have only completed 1 flash, which is the BP50NB40 1.03-MK firmware. This first flash removes the firmware encryption and does enable libredrive but this firmware is not UHD compatable.steeledrum wrote: ↑Tue Sep 02, 2025 1:02 am
Can you elaborate on what I missed? I've attached how it looked when I did the flash.
You now need to perform the cross-flash to enable UHD readability. Please go to the SDFtool Flasher thread: viewtopic.php?p=94848#p94848 go to the section: to flash the BP50NB40 SVC:NB52 and follow from step 2. There's even a gif showing the process and there's no need to check the boot loader box at all.
NO!! You should never use that clean 1.0 firmware!! That is for older models (pre 2016) that were flashed when they shouldn't have been.
Cheers
----------------------------------------------------------------------------------------------------------------------------
For UHD enabled drives (AU/NZ/SG + Others) & DIY Single Drive Flasher (WW): https://uhdenableddrives.com

----------------------------------------------------------------------------------------------------------------------------
For UHD enabled drives (AU/NZ/SG + Others) & DIY Single Drive Flasher (WW): https://uhdenableddrives.com
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- Posts: 8
- Joined: Mon Sep 01, 2025 7:30 pm
Re: Cross-flashed LG BP50NB40 (NB52) – UHD not reading, Blu-rays are fine
Apologies, as you're exactly right. I made progress last night after posting this and realizing what I had done wrong. This is now how it shows:MartyMcNuts wrote: ↑Tue Oct 07, 2025 3:29 amThen you are not following the instructions exactly!! Each file selection window tells you what to select in the title.steeledrum wrote: ↑Tue Oct 07, 2025 2:53 amMarty, I have tried this multiple times to no avail. Now I'm concerned, as I cannot even flash to the 1.0 clean firmware you have linked from that link you sent me. For the life of me, I cannot get this to work. Any other ideas?MartyMcNuts wrote: ↑Tue Sep 02, 2025 4:10 am
Yeah, I missed that too! This model must be cross-flashed to either BU40N or BP60NB10 to enable UHD readability (requiring 2 flashes). You have only completed 1 flash, which is the BP50NB40 1.03-MK firmware. This first flash removes the firmware encryption and does enable libredrive but this firmware is not UHD compatable.
You now need to perform the cross-flash to enable UHD readability. Please go to the SDFtool Flasher thread: viewtopic.php?p=94848#p94848 go to the section: to flash the BP50NB40 SVC:NB52 and follow from step 2. There's even a gif showing the process and there's no need to check the boot loader box at all.
NO!! You should never use that clean 1.0 firmware!! That is for older models (pre 2016) that were flashed when they shouldn't have been.
Code: Select all
Drive Information
OS device name: E:
Manufacturer: HL-DT-ST
Product: BD-RE BU40N
Revision: 1.00
Serial number: SIM21217L1554
Firmware date: 2116-12-20 15:28
Bus encryption flags: 17
Highest AACS version: 75
LibreDrive Information
Status: Enabled
Drive platform: MT1959
Firmware type: Original (unpatched)
Firmware version: 1.00
DVD all regions: Yes
BD raw data read: Yes
BD raw metadata read: Yes
Unrestricted read speed: Yes
Re: Cross-flashed LG BP50NB40 (NB52) – UHD not reading, Blu-rays are fine
Clean your UHD disc or try a different disc. LG drives are not as good as Pioneer readers.
No insult intended but are you a bot? Your question about firmware on the BP50NB40 has been asked and answered probably 50 times before and a bot may just use those postings to make a realistic question.
"Clean your disc" has also been the answer 100's of times.
No insult intended but are you a bot? Your question about firmware on the BP50NB40 has been asked and answered probably 50 times before and a bot may just use those postings to make a realistic question.
"Clean your disc" has also been the answer 100's of times.
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Re: Cross-flashed LG BP50NB40 (NB52) – UHD not reading, Blu-rays are fine
It's a brand new disc. I literally just took the case out of the plastic wrap. I'll still give it a clean. I'll try a different disc that's older. Perhaps it's something with the new one.jinx100 wrote: ↑Tue Oct 07, 2025 1:41 pmClean your UHD disc or try a different disc. LG drives are not as good as Pioneer readers.
No insult intended but are you a bot? Your question about firmware on the BP50NB40 has been asked and answered probably 50 times before and a bot may just use those postings to make a realistic question.
"Clean your disc" has also been the answer 100's of times.
No, I'm not a bot. What a bot thing to say right?
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Re: Cross-flashed LG BP50NB40 (NB52) – UHD not reading, Blu-rays are fine
Apologies. Appears it was the disc.
Re: Cross-flashed LG BP50NB40 (NB52) – UHD not reading, Blu-rays are fine
Nice pun!
What confused you in Marty's instructions about flashing the BP50NB40 drive? What changes could be made to make it more clear?