it won't let me log into my account, it asks for my password (which it never did before on startup) and when i enter it the screen goes black and then back to the purple login page. as soon as i turn the computer on a "system error detected" message appears, and again when i try to sign in. It's not a password issue, as when I enter in a different password it gives me an "incorrect password" message, but not when I use the correct one. It does let me log in as a guest but I urgently need to retrieve a very important file from my account.
Any help would be greatly appreciated! (please bear in mind that I have absolutely no idea how linux works and have great difficulties understanding the commands etc!!) Thanks