GPG Error

I have fresh installation of ubuntu 14.04 now. When I updated my system, I faced the following GPG Error:

W: GPG error: trusty Release: The following signatures were invalid: BADSIG 40976EAF437D05B5 Ubuntu Archive Automatic Signing Key <>

As it is saying that “BADSIG 40976EAF437D05B5” signature is invalid. To solve this, I run the following command to import the keys:

sudo apt-key adv --keyserver --recv-keys 6AF0E1940624A220 40976EAF437D05B5


  1. apt-key: It is used to manage the list of keys used by apt to authenticate packages. Packages which have been authenticated using these keys will be considered trusted.
  2. adv: Pass advanced options to gpg. With adv –recv-key you can download the public key.
  3. For more details, read

But, it didn’t solve the issue. Then, I found a trick to remove this error. This was like given below:

Open your source.list using your favorite text editor, i.e.

$ sudo vim /etc/apt/sources.list

locate and replace it with

So, I remove the ‘in.’ prefix in each of the addresses to convert them to addresses of the main server. This solved my problem.


I’m so khush khush

It was my dream to learn Shastra Vidya and I’m so happy that finally I started classes of Gatka. Today, it was my second day of training and I learnt the technique to grip the sword and move forward to attack. Aha! wonderful day it was. But rest of the day, I was busy with my Java assignments.

LaTeX – Defines the Beauty of Documents

When I came to know about LaTeX for the very first time in my 6 weeks training, I was little excited to know what the heck is LaTeX. I was excited also because I was going to learn something new. But I never knew that the word I didn’t hear before will become my favorite one so soon like this. But this happened. Yes, I broke up my 18 years healthy relationship with WYSIWYG after seeing the beauty of LaTeX. How self-seeking I am? Isn’t it? 😉 Continue reading