Bad Shim Signature

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1

Hi.
I have a dual boot of Windows 11 and Fedora 43. Both were working normally. Secure boot and fTPM 2.0 were activated. I had some problems recently and did reset the BIOS. Now I activated fTPM.
The problem occurring here is: if I turn on the computer and try to boot on Windows, it shows a message stating:

error: ../../grub-core/kern/efi/sb.c:192:bad shim signature.

If I try to boot on Windows and after that on Fedora, neither works, but if I restart the PC and try to boot directly on Fedora, it works. How can I fix this?

2

I was able to resolve the problem. Just needed to update/recover the shim signature. I followed the steps in the first method in this guide in Microsoft’s site. Really easy and worked well.

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