Skip to main content

Repair information for the Dell Inspiron 15-5559 laptop.

9 Questions View all

Operating System loader has no signature. Incompatible with secure boo

Operating system loader has no signature. Incompatible with secure boot. All Bootable device failed secure boot verification.

Answered! View the answer I have this problem too

Is this a good question?

Score 1
1 Comment

Tried installing your laptop?

by

Add a comment

3 Answers

Chosen Solution

Try pressing F2 on bootup and then go into set and turn SecureBook off. That should let it boot up fully.

Was this answer helpful?

Score 2

4 Comments:

No Bootable device found.

by

Can you verify that the HD is good?

by

No bootable devices found.... how to fix it?

by

1. How is disabling SecureBoot a "solution"? and 2. It didn't work anyway. Confirmed that there's no issue with the hard drive. Does anyone have any other suggestions?

by

Add a comment
Most Helpful Answer

My colleagues Laptop Dell Inspiron 15-3567 (System Bios: 2.9.0, ePSA: Build 4304.14 UEFI ROM) with OS Windows 10, boot failed with error "Operating System Loader Signature Loader failed signature verification. WARNING: The file may have been tempered with! All bootable devices failed Secure Boot verification." (Note that I am writing this down so that this post shows up in Google Search). The steps listed below worked for me:

1. On Startup, press F12, and on the options, Select BIOS Setup.

2. Reset Bios to default settings (in my case I did Factory Reset).

3. Restart Laptop, go to BIOS setup again.

4. Firstly, Disable Secure Boot Option.

5. Then, Select Boot Sequence menu.

6. Manually ADD additional line with the name "Windows Boot Manager".

7. Select file /EFI/BOOT/BOOTX64.EFI for the entry created in step 7.

8. Exit and Restart. If the Laptop does not boot then uncheck default UEFI boot option in Boot Sequence menu from BIOS, so that the Laptop boots from the boot entry created above.

Was this answer helpful?

Score 3

4 Comments:

I had the exact same problem with my Dell computer and tried several suggested solutions but none worked until I found yours. And it worked, fantastic!

Thank you so much!

by

Step 6 Manually Add Windows boot manager... going in Add button doesn't show WIN boot manager.

How to add...

by

I followed Raj's solution but now when booting I get the error “No bootable devices found.”

Any ideas?

by

Your mistake caused me to lose the win option I was using? You don't deserve to be a guide, please don't post anything else. One day it will harm your family members

by

Add a comment

bro i also had the same problem but i tried it by my own method

when you turn on press F12 as the moment you see dell symbol

Then i dont rember the exact but select last option below bios setup

then after reaching there ther will be futhur two option you try both one at a time while doing this you will see dell  warning to change that setting but you do that .It worked for i too search the  whole internet but didnt found the solution anywhere  but this my method worked  for me hope it  will work for you

Was this answer helpful?

Score 0
Add a comment

Add your answer

Raman. will be eternally grateful.
View Statistics:

Past 24 Hours: 19

Past 7 Days: 71

Past 30 Days: 289

All Time: 27,899