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MBR denied while manually making Unraid boot usb

Featured Replies

Hi Unraid Community,

I'm currently trying to build my first Unraid server and I've come to the point where I want to install Unraid.

During the setup of the Boot USB I've stumbled upon some inconveniences:

Firstly the USB creation tool doesn't detect the (formatted to FAT32) USB Stick:

 

1311105913_meeronzin.thumb.PNG.fe87eb6832a8aad88dea586f160c2c1e.PNG

So of course I tried doing it manually which gave me a "MBR DENIED" error:

1430066238_unraidonzin.thumb.PNG.9d2e9f521dab5ca1ad0b22afcf8ff750.PNG

After some research I didn't find anything that could help me nor at all...

 

Could someone please help me out?

Yours sincerly,

Coolmeesje

PS: there is nothing wrong with my USB-Stick since I was able to make it a bootable disk countless times before (for Kubuntu/Win10).

Edited by Coolmeesje
the pictures didnt work and a small spelling mistake

  • Community Expert

Your screenshots aren't working.

 

Now that you have been approved, you should be able to attach them directly to your NEXT post. In future, please always attach instead of linking to an external site.

  • Author
Just now, trurl said:

Your screenshots aren't working.

 

Now that you have been approved, you should be able to attach them directly to your NEXT post. In future, please always attach instead of linking to an external site.

Thx, and I will. (I've also changed in in the post)

  • Community Expert

Have you tried with a USB 2 port? Not sure it matters when creating the flash on another computer, but I do know many people have problems with flash booting Unraid in a USB 3 port.

 

Also, are you sure there is only one partition on the flash?

  • Author
23 minutes ago, trurl said:

Have you tried with a USB 2 port? Not sure it matters when creating the flash on another computer, but I do know many people have problems with flash booting Unraid in a USB 3 port.

 

Also, are you sure there is only one partition on the flash?

It's a Usb 2.0 port and a usb 2.0 stick, and I'm sure it has just one partition

 

Edited by Coolmeesje
more in detial

  • Community Expert

Have you tried running the USB creator tool or the Cmd.exe in Administrator mode.    I believe this is required.

  • Author
28 minutes ago, itimpi said:

Have you tried running the USB creator tool or the Cmd.exe in Administrator mode.    I believe this is required.

I did and it wasn't the solution sadly.

USB stick might not have a GUID whats the brand of the stick?

  • Author
Just now, ijuarez said:

USB stick might not have a GUID whats the brand of the stick?

Idk what GUID is, but the brand of my stick is HEMA. (A local store's home brand from the Netherlands)

  • Community Expert
4 minutes ago, Coolmeesje said:

Idk what GUID is, but the brand of my stick is HEMA. (A local store's home brand from the Netherlands)

GUID is the globally unique identifier required to assign an Unraid license to the flash drive. Without it you won't be able to use it with Unraid. Not saying it doesn't have a GUID, we don't know. And I don't know if that is any reason it shouldn't be able to prepare it for booting.

 

Might be simpler if you just try a more reputable flash drive.

  • Author
41 minutes ago, trurl said:

GUID is the globally unique identifier required to assign an Unraid license to the flash drive. Without it you won't be able to use it with Unraid. Not saying it doesn't have a GUID, we don't know. And I don't know if that is any reason it shouldn't be able to prepare it for booting.

 

Might be simpler if you just try a more reputable flash drive.

It does have a GUID. (I don't know how senitive it is so I did 'blur' some numbers)

Knipsel.PNG

  • Community Expert

How large is the flash? 32GB is maximum for FAT32.

  • Author
1 minute ago, trurl said:

How large is the flash? 32GB is maximum for FAT32.

its 8gb

How about using something like Rufus to pre-format the drive w/ MBR?    It helped me when I had a USB stick not recognized during MSI BIOS updates.

 

https://rufus.ie/

 

PS - I have never had luck with Unraid's USB flash creator, and have always had to do the manual copy of data + makebootable in admin mode.

 

Edited by danull
the PS

  • Author
44 minutes ago, danull said:

How about using something like Rufus to pre-format the drive w/ MBR?    It helped me when I had a USB stick not recognized during MSI BIOS updates.

 

https://rufus.ie/

 

PS - I have never had luck with Unraid's USB flash creator, and have always had to do the manual copy of data + makebootable in admin mode.

 

Thx so much!

Ive found a loophole where i made it MBR with a Kubuntu iso using Rufus (the .zip for unraid won't work in rufus apperently). I then deleted all contents that was extracted from the iso. Extracted the unraid zip to the usb drive. Ran the cmd commandline and no more MBR rubbish!

wahoo.PNG

glad to hear it!

Just a theory: virtually all USB flash devices come preformatted with either FAT32 or ExFat.  If the device has some other file system, or perhaps no file system or perhaps cleared out MBR then Windows probably doesn't recognize the device in such a manner that function used to populate the device list in our Flash Creator doesn't see it.

 

btw 32GB limitation is only for windows being able to format it using FAT32, larger devices windows will format using ExFat.  Our Flash Creator can format devices larger than 32GB with FAT32.

  • Community Expert
41 minutes ago, limetech said:

btw 32GB limitation is only for windows being able to format it using FAT32, larger devices windows will format using ExFat.  Our Flash Creator can format devices larger than 32GB with FAT32.

I knew there were ways beyond the native windows to format >32GB FAT32 but didn't know the Flash Creator would do it.

  • 4 years later...

Hello,

 

I have the same problem to replace my usb drive. Formatted it with RUFUS and no luck. Tried the trick to load Kubuntu as an ISO image with RUFUS and then wiping it and replace it with my USB backup. Still same issue that windows cannot update the MBR when running the make bootable.bat.

Can anyone help here?

  • Community Expert

Have you tried the new USB tool?

  • 11 months later...

Hi, just to close this out.

The issue was with my tablet. When I connected to my laptop and generate the USB key, all was good.

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