webmin install and login for the first time on ubuntu linux

To instal webmin on ubuntu use

 sudo apt-get install webmin webmin-core

The problem i faced was that I could not login for the first time. The solution is

1.

add line

username:x:0

(where username is a valid user of your system) to your/etc/webmin/miniserv.users file

2.

modify file /etc/webmin/webmin.acl

make the line

root: acl change-users ... etc. 

to look like

 username: acl change-users ... etc. 

Do not change anything in the existing line in your file, just replace root with any valid user.