我当时正在尝试格式化 USB 密钥，不小心删除了一个 157MB 的分区，我怀疑它是 Ubuntu 的启动分区。但实际上我不知道我删除了什么，可能是 EFI 系统分区。
我确信我选择了要格式化的 USB，并跳过了所有警报，因为在此之前我收到了 USB 正在使用的消息。
我的戴尔 XPS 17 英寸笔记本电脑配有 1T 硬盘，装有 Windows 和Ubuntu 桌面 20.04.3 LTS已安装。这是当前情况的图片，key是我已经格式化的分区：
从 Live USB Ubuntu 运行：
$ sudo fdisk -l
Disk /dev/loop0: 2.1 GiB, 2160009216 bytes, 4218768 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
Disk /dev/loop1: 55.45 MiB, 58130432 bytes, 113536 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
Disk /dev/loop2: 65.1 MiB, 68259840 bytes, 133320 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
Disk /dev/loop3: 219 MiB, 229638144 bytes, 448512 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
Disk /dev/loop4: 50.98 MiB, 53432320 bytes, 104360 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
Disk /dev/loop5: 32.3 MiB, 33865728 bytes, 66144 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
Disk /dev/nvme0n1: 953.89 GiB, 1024209543168 bytes, 2000409264 sectors
Disk model: Micron 2300 NVMe 1024GB
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
Disk identifier: 9799531D-8078-41B9-9BFA-4D8E5889A40D
Device Start End Sectors Size Type
/dev/nvme0n1p1 2048 309247 307200 150M Linux filesystem
/dev/nvme0n1p2 309248 571391 262144 128M Microsoft reserved
/dev/nvme0n1p3 571392 1176300355 1175728964 560.6G Microsoft basic data
/dev/nvme0n1p4 1957793792 1959821311 2027520 990M Windows recovery environment
/dev/nvme0n1p5 1959821312 1997438975 37617664 18G Windows recovery environment
/dev/nvme0n1p6 1997441024 2000377855 2936832 1.4G Windows recovery environment
/dev/nvme0n1p7 1176301568 1957793791 781492224 372.7G Linux filesystem
Partition table entries are not in disk order.
Disk /dev/sda: 29.12 GiB, 31260704768 bytes, 61056064 sectors
Disk model: Cruzer Fit
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: dos
Disk identifier: 0x2cf4ba3a
Device Boot Start End Sectors Size Id Type
/dev/sda1 * 0 5999871 5999872 2.9G 0 Empty
/dev/sda2 5271500 5279499 8000 3.9M ef EFI (FAT-12/16/32)
/dev/sda3 6000640 61056063 55055424 26.3G 83 Linux
$ sudo gdisk -l /dev/sda
GPT fdisk (gdisk) version 1.0.5
Partition table scan:
MBR: MBR only
BSD: not present
APM: not present
GPT: not present
***************************************************************
Found invalid GPT and valid MBR; converting MBR to GPT format
in memory.
***************************************************************
Warning! Secondary partition table overlaps the last partition by
33 blocks!
You will need to delete this partition or resize it in another utility.
Disk /dev/sda: 61056064 sectors, 29.1 GiB
Model: Cruzer Fit
Sector size (logical/physical): 512/512 bytes
Disk identifier (GUID): 8CF0A28E-AAD6-4288-B195-4CF693FFA61F
Partition table holds up to 128 entries
Main partition table begins at sector 2 and ends at sector 33
First usable sector is 34, last usable sector is 61056030
Partitions will be aligned on 4-sector boundaries
Total free space is 5992606 sectors (2.9 GiB)
Number Start (sector) End (sector) Size Code Name
2 5271500 5279499 3.9 MiB EF00 EFI system partition
3 6000640 61056063 26.3 GiB 8300 Linux filesystem
机器无法再启动，每次启动时它都会进入 DELL 的一些扫描工具。
如果我按 F12，我可以看到 Ubuntu 和 Windows 启动管理器的启动对话框，但如果我选择它们，我会被告知“未找到启动设备”。我目前正在使用“试用 Ubuntu”从 Live Ubuntu USB 进行写入。
我想知道，看图片时我删除了什么？第二个 134MB 分区显示为 Microsoft 保留分区，所以我想我格式化的关键分区是 Ubuntu 启动分区？
您认为如果我在分区中安装 Ubuntu 启动，key我就可以再次启动 Win/Ubuntu 分区吗？
您能告诉我应该采取哪些措施来确保我不会再制造混乱吗？我需要一些指导来增强信心。
是我删除了 EFI 分区还是其他原因？也许我应该在key分区中安装 GRUB？