Can't mount or fix corrupt NTFS partition on working HDD
Solution 1:
You have a (corrupted) Windows NTFS partition. By being closed source, Microsoft Windows makes it difficult to impossible for Linux to repair its secret disk structure. Like the error message says In the first case run chkdsk /f on Windows then reboot into Windows twice. Windows MIGHT be able to fix the disk. Ask how to boot Windows from some alternate medium on some Windows support site, not AskUbuntu. Otherwise, you will have to restore your data from backups (you do have backups, don't you?).