更新 24 小时，花了一整天时间。感谢您的帮助。新硬盘，Ubuntu 安装，然后 testdisk 和 e2fsck 可能获得了对失败/阻止的 ext4 分区（在 Gparted 中丢失了其 ext4 格式描述）的几乎完全访问权限。我还没有看到 ext4 分区操作系统现在是否可以启动。怀疑它。不幸的是，我不确定在什么时候完全恢复访问权限，是 testdisk 的第一部分起作用了，还是随后的 e2fsck 起作用了。我放弃了 e2fsck 的某种方式......关于 testdisk，一个令人沮丧的是，对于我这个初学者来说，这是一个终端操作的程序，所以我浪费了大量的时间来寻找已安装的程序。希望这一切能对某人有所帮助。
######################详细信息................ 使用 Ubuntu Live CD 和建议的方法没有取得任何进展 - 建议的终端任务在访问/修复 ext4 分区方面没有取得任何进展。新硬盘已准备就绪，我加载了 Ubuntu，然后进一步查看了旧硬盘。它的 NTFS 分区仍然很好，但什么都无法访问 ext4 分区。
然而，我随后尝试了测试磁盘程序，它经历了各种过程并建议了一种使用 e2fsck 的特定方法。
然后 ext4 分区变得可以访问了 ?????? 所以 testdisk 让我到达了那里（我不知道怎么做到的），然后我可以将我的所有数据复制到新硬盘上。我想我丢失了我的书签和密码，因为我找不到它们，但我把它们放在别处了。
网上有一个问题说，当分区变得非常满时，就会发生这种情况，但我的情况似乎并非如此。我对操作系统等知之甚少，我只是想象 ext4 格式/文件“树”的顶部被损坏了。该磁盘最多只有 2 个坏扇区。我认为多年来升级各种 Ubuntu 版本引入了一些我忽略的问题，或者可能是硬盘在这个扇区出现故障。
#原始问题，，，，，，，我已经在笔记本电脑和外部硬盘上使用 Ubuntu 几年了，它有两个分区，一个用于备份（仍然运行良好），一个用于 Ubuntu。突然，Ubuntu 14.04 无法启动，我通过 CD 驱动器上的 Ubuntu 执行此操作。Gparted 中显示的 Ubuntu 分区没有定义文件系统或挂载点，并标记为黑色。
我的问题是可能发生了什么，这个分区中的数据和 Ubuntu 操作系统是否可能仍然存在，或者这个分区是否已被清除，可能是被恶意软件清除的（有可能吗？）？如何继续？我想这不是将其文件系统重新定义为 ext4 的简单问题？
我的大部分数据都已备份，并且我花了几个小时查看这些内容，尽管对分区和 Grub 等的了解有限。
$ sudo e2fsck -n /dev/sda2
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Directories count wrong for group #320 (0, counted=1361).
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Free inodes count wrong for group #321 (8192, counted=8184).
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Free inodes count wrong for group #322 (8192, counted=4039).
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Free inodes count wrong for group #323 (8192, counted=3958).
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Free inodes count wrong for group #324 (8192, counted=4022).
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Free inodes count wrong for group #325 (8192, counted=4061).
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Free inodes count wrong for group #326 (8192, counted=4172).
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Free inodes count wrong for group #327 (8192, counted=4093).
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Free inodes count wrong for group #328 (8192, counted=4076).
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Free inodes count wrong for group #329 (8192, counted=4048).
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Free inodes count wrong for group #330 (8192, counted=4056).
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Free inodes count wrong for group #331 (8192, counted=4119).
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Free inodes count wrong for group #332 (8192, counted=4001).
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Free inodes count wrong for group #333 (8192, counted=4035).
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Free inodes count wrong for group #334 (8192, counted=4057).
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Free inodes count wrong for group #335 (8192, counted=3895).
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Free inodes count wrong for group #336 (8192, counted=5).
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Directories count wrong for group #336 (0, counted=844).
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Free inodes count wrong for group #337 (8192, counted=6023).
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Directories count wrong for group #337 (0, counted=47).
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Free inodes count wrong for group #352 (8192, counted=2302).
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Directories count wrong for group #352 (0, counted=698).
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Free inodes count wrong for group #368 (8192, counted=0).
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Directories count wrong for group #368 (0, counted=1025).
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Free inodes count wrong for group #369 (8192, counted=5634).
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Directories count wrong for group #369 (0, counted=334).
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Free inodes count wrong for group #384 (8192, counted=3342).
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Directories count wrong for group #384 (0, counted=1358).
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Free inodes count wrong for group #400 (8192, counted=106).
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Directories count wrong for group #400 (0, counted=1142).
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Free inodes count wrong for group #401 (8192, counted=0).
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Directories count wrong for group #401 (0, counted=135).
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Free inodes count wrong for group #402 (8192, counted=7820).
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Directories count wrong for group #402 (0, counted=82).
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Free inodes count wrong for group #416 (8192, counted=0).
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Directories count wrong for group #416 (0, counted=1313).
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Free inodes count wrong for group #417 (8192, counted=6760).
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Directories count wrong for group #417 (0, counted=49).
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Free inodes count wrong for group #432 (8192, counted=2182).
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Directories count wrong for group #432 (0, counted=1362).
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Free inodes count wrong for group #448 (8192, counted=1575).
Fix? no
Directories count wrong for group #448 (0, counted=1362).
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Free inodes count wrong for group #464 (8192, counted=289).
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Directories count wrong for group #464 (0, counted=1318).
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Free inodes count wrong for group #480 (8192, counted=0).
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Directories count wrong for group #480 (0, counted=1280).
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Free inodes count wrong for group #481 (8192, counted=4735).
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Directories count wrong for group #481 (0, counted=83).
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Free inodes count wrong for group #496 (8192, counted=2610).
Fix? no
Directories count wrong for group #496 (0, counted=1287).
Fix? no
Free inodes count wrong for group #512 (8192, counted=3470).
Fix? no
Directories count wrong for group #512 (0, counted=1272).
Fix? no
Free inodes count wrong for group #528 (8192, counted=3466).
Fix? no
Directories count wrong for group #528 (0, counted=1262).
Fix? no
Free inodes count wrong for group #544 (8192, counted=3333).
Fix? no
Directories count wrong for group #544 (0, counted=1295).
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Free inodes count wrong for group #560 (8192, counted=1314).
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Directories count wrong for group #560 (0, counted=1312).
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Free inodes count wrong for group #576 (8192, counted=38).
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Directories count wrong for group #576 (0, counted=1211).
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Free inodes count wrong for group #577 (8192, counted=7500).
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Directories count wrong for group #577 (0, counted=75).
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Free inodes count wrong for group #592 (8192, counted=2756).
Fix? no
Directories count wrong for group #592 (0, counted=1297).
Fix? no
Free inodes count wrong for group #608 (8192, counted=397).
Fix? no
Directories count wrong for group #608 (0, counted=1275).
Fix? no
Free inodes count wrong for group #624 (8192, counted=2240).
Fix? no
Directories count wrong for group #624 (0, counted=1327).
Fix? no
Free inodes count wrong for group #640 (8192, counted=1989).
Fix? no
Directories count wrong for group #640 (0, counted=1263).
Fix? no
Free inodes count wrong for group #656 (8192, counted=407).
Fix? no
Directories count wrong for group #656 (0, counted=1330).
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Free inodes count wrong for group #657 (8192, counted=7387).
Fix? no
Free inodes count wrong for group #672 (8192, counted=3049).
Fix? no
Directories count wrong for group #672 (0, counted=1324).
Fix? no
Free inodes count wrong for group #688 (8192, counted=0).
Fix? no
Directories count wrong for group #688 (0, counted=952).
Fix? no
Free inodes count wrong for group #689 (8192, counted=6532).
Fix? no
Directories count wrong for group #689 (0, counted=376).
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Free inodes count wrong for group #704 (8192, counted=3494).
Fix? no
Directories count wrong for group #704 (0, counted=1327).
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Free inodes count wrong for group #720 (8192, counted=3238).
Fix? no
Directories count wrong for group #720 (0, counted=1333).
Fix? no
Free inodes count wrong for group #736 (8192, counted=3468).
Fix? no
Directories count wrong for group #736 (0, counted=1310).
Fix? no
Free inodes count wrong for group #737 (8192, counted=5388).
Fix? no
Free inodes count wrong for group #752 (8192, counted=4234).
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Directories count wrong for group #752 (0, counted=1317).
Fix? no
Free inodes count wrong for group #753 (8192, counted=4523).
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Free inodes count wrong for group #768 (8192, counted=2632).
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Directories count wrong for group #768 (0, counted=1311).
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Free inodes count wrong for group #769 (8192, counted=4607).
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Free inodes count wrong for group #784 (8192, counted=3858).
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Directories count wrong for group #784 (0, counted=1310).
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Free inodes count wrong for group #800 (8192, counted=3195).
Fix? no
Directories count wrong for group #800 (0, counted=1309).
Fix? no
Free inodes count wrong for group #816 (8192, counted=94).
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Directories count wrong for group #816 (0, counted=1061).
Fix? no
Free inodes count wrong for group #817 (8192, counted=3151).
Fix? no
Directories count wrong for group #817 (0, counted=248).
Fix? no
Free inodes count wrong for group #832 (8192, counted=2173).
Fix? no
Directories count wrong for group #832 (0, counted=1309).
Fix? no
Free inodes count wrong for group #848 (8192, counted=3180).
Fix? no
Directories count wrong for group #848 (0, counted=1310).
Fix? no
Free inodes count wrong for group #864 (8192, counted=1128).
Fix? no
Directories count wrong for group #864 (0, counted=1138).
Fix? no
Free inodes count wrong for group #865 (8192, counted=7546).
Fix? no
Free inodes count wrong for group #880 (8192, counted=2464).
Fix? no
Directories count wrong for group #880 (0, counted=1342).
Fix? no
Free inodes count wrong for group #896 (8192, counted=0).
Fix? no
Directories count wrong for group #896 (0, counted=1281).
Fix? no
Free inodes count wrong for group #897 (8192, counted=7746).
Fix? no
Directories count wrong for group #897 (0, counted=69).
Fix? no
Free inodes count wrong for group #912 (8192, counted=3639).
Fix? no
Directories count wrong for group #912 (0, counted=1313).
Fix? no
Free inodes count wrong for group #928 (8192, counted=2391).
Fix? no
Directories count wrong for group #928 (0, counted=1362).
Fix? no
Free inodes count wrong for group #944 (8192, counted=3038).
Fix? no
Directories count wrong for group #944 (0, counted=1362).
Fix? no
Free inodes count wrong for group #960 (8192, counted=2423).
Fix? no
Directories count wrong for group #960 (0, counted=1087).
Fix? no
Free inodes count wrong for group #976 (8192, counted=8007).
Fix? no
Directories count wrong for group #976 (0, counted=1).
Fix? no
Free inodes count wrong for group #992 (8192, counted=8191).
Fix? no
Directories count wrong for group #992 (0, counted=1).
Fix? no
Free inodes count wrong for group #1008 (8192, counted=8190).
Fix? no
Directories count wrong for group #1008 (0, counted=1).
Fix? no
Free inodes count wrong for group #1024 (8192, counted=8186).
Fix? no
Directories count wrong for group #1024 (0, counted=3).
Fix? no
Free inodes count wrong for group #1040 (8192, counted=436).
Fix? no
Directories count wrong for group #1040 (0, counted=330).
Fix? no
Free inodes count wrong for group #1041 (8192, counted=7091).
Fix? no
Directories count wrong for group #1041 (0, counted=73).
Fix? no
Free inodes count wrong for group #1056 (8192, counted=7786).
Fix? no
Directories count wrong for group #1056 (0, counted=3).
Fix? no
Free inodes count wrong for group #1088 (8192, counted=8039).
Fix? no
Directories count wrong for group #1088 (0, counted=1).
Fix? no
Free inodes count wrong for group #1120 (8192, counted=8183).
Fix? no
Directories count wrong for group #1120 (0, counted=8).
Fix? no
Free inodes count wrong for group #1136 (8192, counted=8191).
Fix? no
Directories count wrong for group #1136 (0, counted=1).
Fix? no
Free inodes count wrong for group #1152 (8192, counted=7849).
Fix? no
Directories count wrong for group #1152 (0, counted=5).
Fix? no
Free inodes count wrong for group #1184 (8192, counted=8191).
Fix? no
Directories count wrong for group #1184 (0, counted=1).
Fix? no
Free inodes count wrong for group #1344 (8192, counted=8100).
Fix? no
Directories count wrong for group #1344 (0, counted=3).
Fix? no
Free inodes count wrong for group #1360 (8192, counted=8191).
Fix? no
Directories count wrong for group #1360 (0, counted=1).
Fix? no
Free inodes count wrong for group #1408 (8192, counted=5).
Fix? no
Directories count wrong for group #1408 (0, counted=1299).
Fix? no
Free inodes count wrong for group #1409 (8192, counted=7288).
Fix? no
Directories count wrong for group #1409 (0, counted=4).
Fix? no
Free inodes count wrong for group #1424 (8192, counted=4415).
Fix? no
Directories count wrong for group #1424 (0, counted=680).
Fix? no
Free inodes count wrong for group #1472 (8192, counted=638).
Fix? no
Directories count wrong for group #1472 (0, counted=591).
Fix? no
Free inodes count wrong for group #1473 (8192, counted=84).
Fix? no
Directories count wrong for group #1473 (0, counted=550).
Fix? no
Free inodes count wrong for group #1474 (8192, counted=5668).
Fix? no
Directories count wrong for group #1474 (0, counted=201).
Fix? no
Free inodes count wrong (12222453, counted=11367656).
Fix? no
/dev/sda2: ********** WARNING: Filesystem still has errors **********
11 inodes used (0.00%, out of 12222464)
722 non-contiguous files (6563.6%)
495 non-contiguous directories (4500.0%)
# of inodes with ind/dind/tind blocks: 2/2/2
Extent depth histogram: 517155/125
815037 blocks used (1.67%, out of 48876800)
0 bad blocks
1 large file
418807 regular files
79999 directories
57 character device files
26 block device files
0 fifos
9 links
80790 symbolic links (62315 fast symbolic links)
5 sockets
------------
579654 files