I accidentally deleted the /etc/shadow file while experimenting with commands (yeah a newbie!). Now I'm not being able to use sudo and after logging out not being able to login. This all is obvious. Then I created another crunchbang virtual machine, booted from it and mounted the virtual disk of the previous VM. Strangely I can see that the /etc/shadow file and also the 'shadow-' both are still present in the previous virtual disk. I again booted the older VM just to recheck but still not able to login. What is the problem???
Config : CrunchBang 10 as guest on Win7 32 bit using virtual box 4.1.8.
EDIT : Problem FIXED
BIG BLUNDER!!! The shadow was not there, just shadow-. Just copied /etc/shadow- to /etc/shadow then booted from the older VM. Boot successful!!!. Thanks for help and sorry for the unnecessary trouble.