Document check-in problem /loss of data/

Dear Community Members, 

Recently, I've had a Document Check-in problem in my client program. The check-in process was delayed somehow after I gave a check-in my document command to the M-Files user program. I've waited a while, then my computer suddenly restarted and my checked-in document completely disappeared and I cannot find it anywhere... Even from the admin tool program. If someone had the same situation please kindly advise. And can I find my file again? Thank you. 

Best regards, 

Baigal