Category Archives: General

How to detect USB in Virtual Box on Ubuntu

Start the Virtual Box

Goto Setting

Select USB


Tick the Checkbox Enable USB Controller and Enable USB 2.0 (EHCI) Controller


When you tick the checkbox in Enable USB 2.0 (EHCI) Controller you will see the following error


USB 2.0 is currently enabled for this virtual machine. However, this requires the Oracle VM VirtualBox Extension Pack to be installed.

Please install the Extension Pack from the VirtualBox download site. After this you will be able to re-enable USB 2.0. It will be disabled in the meantime unless you cancel the current settings changes.

How to solve this error:

First check for your virtual box version. And download the Oracle VM VirtualBox Extension Pack for your virtual box version.

Goto File -> Preferences

Select Extensions


Click the icon and add the file you downloaded. It will ask for installation install it.





After complete the installation you can Tick the Enable USB 2.0 (EHCI) Controller


Then add the usb device



Now Start the OS. The USB you added will be detecting automatically



Before Shutdown the OS you should Unmount the USB.


How to restart the networking service without crashing Ubuntu?

I tried to use

sudo service networking restart


sudo /etc/init.d/network restart

but they both crash the window manager and I can no longer use my keyboard for input into X.


sudo service network-manager restart


Ubuntu uses network-manager instead of the traditional Linux networking model. so you should restart the network-manager service instead of the network service.

Workshop at Delhi

Two days workshop was conducted in Acharya Narendra Dev College Govindpuri, Kalkaji, New Delhi 110019 about  Application of FOSS in Science Education & Research .. It was  jointly organized by NRCFOSS/AU with ANDC, New Delhi.

Here my experience on that……

On 10th April night we start from chennai by tamilnadu express at 10 p.m. It was a nice journey, this is the first time i travel in train a long time(33hours). 12th April Monday morning we reached Nizhamudin station by 8 o’clock. From there we went to NCERT Guest house by prepaid taxi, reached there by 11 o’clock and get ready to go the ANDC college.

we reached the college by 2 o’clock, after had our lunch we start work on the labs, till 6 o’clock we worked there and returned to guest house by 8 o’clock and went sleep by 10 o’clock(today travel tired so slept soon 🙂 )

The second day 13th April we went to ANDC college and setup the labs , evening around 5 o’clock we finished the work now the the labs are ready to workshop. we install ubuntu  in 4 labs, this ubuntu OS is customized by our people with the FOSS Tools.

The third day 14th April, this is the first day of workshop. Morning  9 o’clock the inauguration lots of people came, combined session was goes till lunch, after that there was a parallel session for the different department (Biology,Chemistry,Physics,Maths,Computer Science) peoples.

The fourth day 15th April, this day also started with the parallel session and we thought the customization also to the people in the FOSS Tools, they are really enjoyed to do the customization. After complete the parallel session certificate distribution. Then we people(NRCFOSS Team) went Delhi University South Campus to discuss about the next day session.

The fifth day 16th April, we went Delhi University South Campus, there was a session about FOSS history, philosophy and all. There also we taught the people to install ubuntu in their laptop. Some of them bring their own laptop, for others Delhi University South Campus provides the laptop. After complete the session we went Lotus Temple(great place i seen) and lajpat nagar for shopping but i cant buy anything because the time is around 8 o’clock we went there, the shops are closed one by one we did window shopping only  then we reached the guest by 10 o’clock and packed our things(next day morning have to leave from there so only 😦 ).

The sixth day 17th April, we started from the guest house by 5 o’clock and reached airport by 6. This is the first time i travel in flight. After completed the checking we entered in the flight by 6.45 and settled to their place. The flight(Spice Jet) was started by 7.20 and we reached chennai airport by 9.55

Thats all…… I had a enjoable moments in those days….. 🙂

Use RPM Package in Debian System

Install rpm packages in debina system:

First you have to install the alien package in your system

$sudo apt-get install alien

Convert the rpm package to deb

$sudo alien name_of_file.rpm

This will convert the rpm package to debian package , then using the following command you can install that package in your system

$sudo dpkg -i name_of_file.deb

Extract rpm file in debian system

To extract all of the files in a rpm package give the following command

$rpm2cpio package.rpm | cpio -dimv

Customizing file browsing behavior on linux

Customizing file browsing behavior in GNOME

By default, GNOME uses the Nautilus file manager, which opens a new window each time you open a
folder. You can change this behavior to use one window with Forward and Back buttons.

To change this, double-click on Computer on the desktop, click Edit and then Preferences. You can
also select Places > Computer > Edit > Preferences from the menu panel. Click the Behavior tab
and click on the box next to the text Always open in browser windows.

Customizing file browsing behavior in KDE

By default, KDE uses the Dolphin file manager. To modify the appearance of Dolphin windows, open
the program by clicking the Kickoff Application Launcher > Applications > System > File Manager
icon for Dolphin. At the top of the Dolphin window, click Settings > Configure Dolphin. The tabs in
the Dolphin Preferences window allow you to specify the folder that Dolphin displays when it starts,
the size of the icons it displays, the font it uses to label icons, and many other options.