After installing Windows 10 everything was running fine. I shut the computer down and later tried to start it up and got the error Hard Drive is not readable. I then put the Win 10 installation disk in and tried to reset but got the error "The drive where Windows 10 is installed is locked. I tried System Restore and same issue, no drive. I then went to Command Prompt and tried chkdsk and diskpart, but no drives.
Any suggestions or known fix ?