I cant open my backbox linux. An error message is showing on startup.
 

The error is
'An error occured while mounting / press s to skip mounting or press M for manual mounting'
I pressed S nothing happened.. The screen went to black.
I pressed M a terminal is opened.
I don't know what to do.. Im new in linux.. Please help me.. Currently i cant open my linux. Im stuck

After pressing m, type:

Mount: /dev/sda5 already mounted or busy
Mount: according to mtab, /dev/sda5 is already mount on /

This is the rply..

Do you get anything sensible if you try enteringinto that terminal screen?

If that's the case, it might be useful to know what is on sda1-4?
It would also be useful to know if this system ever worked or if this is a new problem.
If it is a new problem, what changes if any were make to software or hardware immediately prior to this event?.
Since there are hundreds of different Linux distributions, it would be useful to let us know which one you are using?

Backbox in the title - another newbie using a pen testing distro ...