我搞砸了启动菜单和启动分区。现在，我有两个启动菜单和启动分区，但它们都没有自动加载（我必须选择运行 Efi 应用程序，然后选择 HDD）。
有没有办法恢复到一个启动分区？
以下是 bootinfoscript 的结果：
============================= Boot Info Summary: ===============================
=> Grub2 (v1.99) is installed in the MBR of /dev/sda and looks at sector
55486016 of the same hard drive for core.img, but core.img can not be
found at this location.
=> No boot loader is installed in the MBR of /dev/sdb.
sda1: __________________________________________________________________________
File system: vfat
Boot sector type: FAT32
Boot sector info: No errors found in the Boot Parameter Block.
Operating System:
Boot files: /efi/Boot/bootx64.efi /efi/ubuntu/fwupx64.efi
/efi/ubuntu/grubx64.efi /efi/ubuntu/MokManager.efi
/efi/ubuntu/shimx64.efi
sda2: __________________________________________________________________________
File system: ext4
Boot sector type: Grub2 (v1.99)
Boot sector info: Grub2 (v1.99) is installed in the boot sector of sda2
and looks at sector 55454200 of the same hard drive
for core.img, but core.img can not be found at this
location.
Operating System: Ubuntu 16.04.1 LTS
Boot files: /boot/grub/grub.cfg /etc/fstab
sda3: __________________________________________________________________________
File system: swap
Boot sector type: -
Boot sector info:
sda4: __________________________________________________________________________
File system: ext4
Boot sector type: -
Boot sector info:
Operating System:
Boot files:
sda5: __________________________________________________________________________
File system: ext4
Boot sector type: -
Boot sector info:
Operating System:
Boot files:
sdb1: __________________________________________________________________________
File system: vfat
Boot sector type: Unknown
Boot sector info: No errors found in the Boot Parameter Block.
Operating System:
Boot files: /efi/Boot/bkpbootx64.efi /efi/Boot/bootx64.efi
/efi/ubuntu/grubx64.efi /efi/ubuntu/MokManager.efi
/efi/ubuntu/shimx64.efi
sdb2: __________________________________________________________________________
File system:
Boot sector type: -
Boot sector info:
Mounting failed: mount: unknown filesystem type ''
sdb3: __________________________________________________________________________
File system: ntfs
Boot sector type: Windows Vista/7: NTFS
Boot sector info: No errors found in the Boot Parameter Block.
Operating System:
Boot files: /Windows/System32/winload.exe
sdb4: __________________________________________________________________________
File system: ntfs
Boot sector type: Windows Vista/7: NTFS
Boot sector info: No errors found in the Boot Parameter Block.
Operating System:
Boot files:
============================ Drive/Partition Info: =============================
Drive: sda _____________________________________________________________________
Disk /dev/sda: 1.8 TiB, 2000398934016 bytes, 3907029168 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: gpt
Partition Boot Start Sector End Sector # of Sectors Id System
/dev/sda1 1 3,907,029,167 3,907,029,167 ee GPT
GUID Partition Table detected.
Partition Start Sector End Sector # of Sectors System
/dev/sda1 2,048 487,423 485,376 EFI System partition
/dev/sda2 487,424 78,612,479 78,125,056 Data partition (Linux)
/dev/sda3 78,612,480 102,049,791 23,437,312 Swap partition (Linux)
/dev/sda4 102,049,792 2,445,799,423 2,343,749,632 Data partition (Linux)
/dev/sda5 2,445,799,424 3,907,028,991 1,461,229,568 Data partition (Linux)
Drive: sdb _____________________________________________________________________
Disk /dev/sdb: 931.5 GiB, 1000204886016 bytes, 1953525168 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disklabel type: gpt
Partition Boot Start Sector End Sector # of Sectors Id System
/dev/sdb1 1 4,294,967,295 4,294,967,295 ee GPT
/dev/sdb1 ends after the last sector of /dev/sdb
GUID Partition Table detected.
Partition Start Sector End Sector # of Sectors System
/dev/sdb1 2,048 206,847 204,800 EFI System partition
/dev/sdb2 206,848 468,991 262,144 Microsoft Reserved Partition (Windows)
/dev/sdb3 468,992 1,952,602,111 1,952,133,120 Data partition (Windows/Linux)
/dev/sdb4 1,952,602,112 1,953,523,711 921,600 Windows Recovery Environment (Windows)
"blkid" output: ________________________________________________________________
Device UUID TYPE LABEL
/dev/sda1 A4C8-0534 vfat
/dev/sda2 77da29bf-6804-45c7-acbf-0b2161119498 ext4
/dev/sda3 3bf35cd6-d20e-452b-864c-85f55497d420 swap
/dev/sda4 9cb69512-d74d-490f-91ec-92e5225dc239 ext4
/dev/sda5 83ef14f3-bf72-4a92-8681-ab6ee73d4620 ext4
/dev/sdb1 1282-7C67 vfat
/dev/sdb2
/dev/sdb3 82F88AEEF88ADFB1 ntfs
/dev/sdb4 F056527156523914 ntfs
================================ Mount points: =================================
Device Mount_Point Type Options
/dev/sda2 / ext4 (rw,relatime,errors=remount-ro,data=ordered)
/dev/sda4 /home ext4 (rw,relatime,data=ordered)
/dev/sdb1 /boot/efi vfat (rw,relatime,fmask=0022,dmask=0022,codepage=437,iocharset=iso8859-1,shortname=mixed,errors=remount-ro)
=========================== sda2/boot/grub/grub.cfg: ===========================