fsck error on boot: /dev/sda2 - can't type slash character
Solution 1:
In such cases it's useful to have a look at the US keyboard layout.
The key on your keyboard to the left of the right Shift key should be / on US keyboards - which is the default unless changed on Linux.
It's also possible to do this without ever typing /. Simply cd .. until you are at /, then cd dev followed by fsck sda2. You don't need to give it the full path.