Since last week, my Google Compute Engine instances do not boot because of this error.
[0m[37m[40m[0m[30m[40m[2J[01;01H[0m[37m[40m Booting `verified image A'
error: /syslinux/vmlinuz.A has invalid signature.
Press any key to continue...
Failed to boot both default and fallback entries.
Does anybody know the cause of this failure?