Thanks for your suggestion. I backed up everything first; and executed the command "bcdedit /set {bootmgr} path \EFI\ubuntu\shimx64.efi" I set the bios to use secure boot and everything works. I get the grub2 menu and can choose to start either Ubuntu or Windows.
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1641793 Title: Invalid Signature detected -- must uncheck secure boot To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/shim/+bug/1641793/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs