Install WICD network manager on Linux Ubuntu/Mint

It may occur that by default your computer won't connect to wireless networks after starting up the system. A way to solve this might be to install the WICD network manager which is available in the Ubuntu repositories.

Just fire up Synaptic Package Manager and search for WICD.
During installation, you will be asked to add system users to the netdev group - check the users that you would like to use WICD with:

Proceed with the installation and launch WICD through Ubuntu's/Mint's main menu. In the program's interface, check the network that you would like to connect with on system startup and try it out by rebooting your machine.

A connection should now automatically be build with the chosen wireless network.

How to delete saved passwords for network drives on Linux desktops

The majority of graphical environments let you choose to remember the passwords you enter somewhere to ease access to something but they usually don't tell you how to delete them again. Most Linux desktop distributions have a tool installed where all your saved passwords for network drives are stored in that is called Passwords and Keys.

You can find the saved passwords right on the first Passwords tab. Right-click the one you want to remove and select Delete. Confirm your choice by clicking Delete again on the window that pops up.

Install Gimp 2.8 on Ubuntu 12.04 and Mint 13

Don't do this on prior releases of the operating systems. There are reports of severe crashes (for me, there were only dependency errors but you never know)!

Gimp version 2.8 is now available as sourcecode and via ppa. It comes with an often requested single-window mode and a few other features. If you have any earlier versions of Gimp installed, purge those first:

sudo apt-get purge gimp*

To install it, add the ppa to your sources, update the apt database and install it:

sudo add-apt-repository ppa:otto-kesselgulasch/gimp

sudo apt-get update
sudo apt-get install gimp

To enable single-window mode, open Gimp and select Windows > Single-Window Mode

Google Earth alternative – Marble (Linux, Windows, Mac)

Google products have the tendancy to not be liked for several reasons, such as installing additional stuff like updaters and managers.
For the popular Google Earth application, there is an alternative, originally developed for the Linux KDE desktop environment, but now available for the major operating systems including Windows and Mac.

Marble lacks the detailed photographic view that Google Earth offers, but includes all regular street maps as well as different other interesting views of the earth, such as night and temperature views.

You can download Marble on their homepage:

Change Log-In Screen Background Image on Ubuntu Linux

If you want to make your Ubuntu installation a little less purple and orange, but don't see a solution that covers the change of log-in screen background picture change, try Simple Lightdm Manager. It is a tool that lets you turn the log-in screen into any image you have on your computer. To install, open a terminal and enter the following commands (adding repository, updating sources, installation):

sudo apt-add-repository ppa:claudiocn/slm

sudo apt-get update

sudo apt-get install simple-lightdm-manager

Afterwards open SLM and browse for an image you want to use:

Additionally you can alter the logo that is displayed on the log-in screen's bottom left corner.
Be aware though, that this does not work with images which are located in encrypted file systems!

Change System Sounds on Windows 7 (Including Startup)

This article will deal with two aspects: handling the regular sounds which are accessible in Control Panel as well as changing the system startup sound, which is hidden inside a .dll file and quite tricky to get at.
The regular sounds can be accessed by entering the Control Panel and browsing to Control Panel\Hardware and Sound\Sounds\Change system sounds. A window with selectible sound schemes will open where you can either select a premade scheme or browse your files to choose other .wav files and save a custom scheme. The checkbox below the list already indicates that you will not find the Startup sound in it - you will need third party software for that.

The reason for this requirement is that the startup sound isn't configurable by "normal" means - it is hidden inside a .dll file, C:\Windows\System32\imageres.dll. Before you make any changes to it, make a backup-copy of it to some safe place and also one on your desktop to work with. Afterwards, download a resource hacker - these tools are used to access the data inside .dll files which can be sound files as well as icons and other things. I prefer ResEdit since it does not need an installation. You can download it here:

In ResEdit, open the copy of imageres.dll you saved to your desktop.

On the left Resources column, find the "WAVE" entry - there is exactly one file in there, which has different names depending on your system language - I'm using American English, which is why it's called 5080 here (replace any occurance of that number here with the one you have for your language). To be able to import your own sound, it also must be in the .wav format and must be called the same as the file you just found.
Now delete the 5080 entry in ResEdit - right-click it and choose Remove from project. Then right-click on some empty space in the Resource column and select Add Resource... > User Definded. A window pops up - select Name identifier and type in WAVE. Now browse the sound file you want to configure as startup sound and hit Open (I don't know the maximum size of the file you can use, you might try to keep it as small as possible - it worked for me with a file size of ~90kb, others have reported more). It will have the wrong name and language defined after you import it, so you have to change that: Right-click the entry and select Rename. Leave the Ordinal identifier checked and enter 5080 into the identifier box, then select the correct language for you (Englisch (United States) if you had 5080) and hit OK. Afterwards save the file in ResEdit.

Now comes the tricky bit which is replacing the imageres.dll in your System32 folder with the one you edited. If you try to just do it, Windows will most likely hit you with the Permission-Denied-club, no matter how many administrative rights you have got. People have reported that it worked for them in save mode. A save option however is to boot off a Linux Live CD (I used Linux Mint 12 Lisa) and replace the file in the Live environment.

Therefore, just download a CD image file from here or any other Linux distribution's homepage, burn it onto a bootable CD and boot from it.

You will boot into the Live environment, from which you can test and install Linux or if you need, fix stuff on your Windows installation. I will go on with the instructions assuming you chose Linux Mint 12 from the link I provided, if you chose differently you will likely know how to accomplish the next steps on your system.
To replace the file, hover your cursor to the top left corner of the screen - an overlay will pop up. Type in terminal and open the first object of the list appearing:

This is the command line and will be needed in a few moments. Hover to the top left corner again and click on the nautilus icon on the left to open a new file manager window:

On the appearing window, have a look at the left column - there are different (or only one) drives listed, you should be able to determine your Windows system drive by its size or contents. Click on it once to show them. What is important now is the value that is shown on the window decoration on top of the window, circled in red here:

You basically need only the first few characters. Now go back to the terminal you opened and enter

sudo su -

to grant yourself administrative rights. Next, you do the copying. For that, use the following command. You can use the tab-key to autocomplete the path segments, so you don't have to write out the whole value from above. Replace my username with yours and weirdvalue with the drive's value:

cp -f /media/weirdvalue/Users/howtoforge/Desktop/imageres.dll /media/weirdvalue/Windows/System32

The file is now replaced and you can reboot, removing the CD when told to. If you encounter problems with the new imageres.dll, just repeat the process and copy the backup you made to the System32 folder instead.

Kill Processes On Ubuntu

When it comes to killing a frozen process, Ubuntu and its derivatives offer a great variety of ways to do so:
You can open the System Monitor to end or kill a running process. Just right-click and annihilate:

Then there is the Force Quit applet. Not that powerful, but does its job in most of the cases:

Working similarly but more powerful is the xkill command line tool. You can also wrap that one into a launcher and use it the same way as an applet.

Another command line tool is killall followed by the name of the process, granting the advantage of not having to know the process ID of the program, which the next tool requires:

kill, provided with the -9 switch and the ID of the process (available with top or ps) shuts down nearly every running process.

If none of those commands help, there is still the option to close the current session with ctrl + alt + backspace. This however comes with the warranty of losing any data you could not save before!

Encrypt Folders (Ubuntu Linux)

To encrypt folders on Linux Ubuntu there is a simple program called Cryptkeeper which, while active, lets you mount and dismount password protected folders.

While unmounted, the encrypted folders are invisible to the user. While mounted, you need to enter the password to access its contents. To create a new encrypted folder just click on the key icon on the system panel and select New encrypted folder.

Make sure to unmount the encrypted folders before you quit Cryptkeeper since the files become accessible if they are mounted and Cryptkeeper is inactive. The files remain invisible if they are unmounted and Cryptkeeper is quit.

Fast Execution Bar (Linux Gnome Desktop)

If you are tired of browsing through your files or the menu to find and open an application you do not use regularly or if you just want to speed up the process of opening a program, there is an application for the Gnome Desktop called GNOME Do which you might like.
Install it as usual with your package manager and start it. To call the execution bar, press SUPER (Windows Key on Windows keyboards) + Space and enter the name or parts of the name of any application, script or executable.

If it is not the desired app that is proposed, you can browse the other possibilties with the Up- and Down- keys. To cancel the bar, hit ESC and to execute the displayed program hit Enter.