A: If you see a text screen with messages like "run fsck manually" or "give root password to continue" one of the computer's file systems is so damaged that the start process of the computer is canceled to carry out a file system check. To this end you have to sign on as superuser (root). Usually the computer will only ask for the password but not the login, i. e. root.

Having successfully logged in you work on a command line with a command prompt such as "repair_filesystem>". Here, you can enter file system check commands such as fsck or similar ones. Search for a line further above with the message

fsck -y /dev/md0

or something similar. This is an example for the command you have to enter. The correct device is very important, in this case /dev/md0. Having entered the command and confirmed by pressing "return" or "enter" on your keyboard, the system will be busy for some time until the prompt "repair_filesystem>" appears again. If the file system check was successful, you can restart the computer usually by pressing CTRL-D on your keyboard.