Possible Duplicate:
How to get back SUDO into working condition?
Here's how I messed up my ubuntu, I wanted to change file permissions of /usr folder and I did that by taking root privilege
sudo -i
I changed the file permission and logged back as my home user, but now I am not able to use sudo command.
I tried to change the permissions back by using chown amd chmod command but that does not seem to work, I even tried running Ubuntu live via Pendrive but I don't know how to get to the filesystem (in which ubuntu is installed) via terminal can anyone help me out here? Help me to get those permissions back to normal?
