Sub-process /usr/bin/dpkg returned an error code (2)

OS: Ubuntu Release 12.04 (precise)

Solution:
 If you faced with problem like :

dpkg: warning: 'ldconfig' not found in PATH or not executable.
dpkg: error: 1 expected program not found in PATH or not executable.

while updating some package, don't worry, there is a right solving to fix this problem.

Add /sbin to your $PATH as root.

Check whether /etc/sudoers file has the correct PATH or not. By default /etc/sudoers should have the path mentioned below. If in case its not present go ahead and add /sbin.

Sample /etc/sudoers file:

Defaults    env_reset
Defaults    secure_path="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin"

Then, relog in and try again.