Change Default Application to Open Files (Linux Mint)

The default application is the one you open a file with on doubleclick. In some cases installed programs automatically turn themselves into the default application for files you were happy with, which you might want to change. To do that, rightclick a file of the chosen format and choose Open With... -> Other Application or Open With Other Application:

On the window that opens, choose an application or command and check the Remember this application for "..." files checkbox to apply your selection for all files of the same format:

Hit Open afterwards.

Log In As Root in Live Mode (Linux Mint)

After crashing your system and getting entertaining colored screens on boot, you may have to consider booting in live mode from a bootable device such as an installation DVD or a USB-device. However you'll need to be able to log in as root in most cases to make changes in configuration files and others to get your system running again. While you can log in as root with a password on your normal system, you can do so in live mode by entering

sudo su -

into the terminal. This logs you in as root so you get to edit your important broken files to be able to boot from your hard drive again.

How to Clean Up Unnecessary Files with Bleachbit (Linux Mint)

Everyone knows the problem of previous installations leaving behind loads of data rubbish on your computer and you may know how hard it can be to remove this data. With bleachbit however you can easily check the data you want to remove and the program does the rest.

You can run it either as normal user or as root, to be sure you really remove every unnecessary file on your harddisk. It is available in the standart Ubuntu repositories.

How to Customize Firefox with about:config

Apart from the wide variety of plugins available for Mozilla Firefox and the option to configure it in the Preferences window, there is another, slightly more hidden feature to customize Firefox' behavior . To access it, enter about:config into your url bar. You will be directed to a warning on first access which you should take seriously:

Once you hit the button you will find yourself inside a giant table of variables with a filterbar at the top which you can use to narrow your results down. Do not change any option when you are not sure of the effects! Here are a few ones you might consider changing to make Firefox a little more handy (if they are not present in your current table, you can add them by rightclicking on it):

dom.max_script_run_time - determines the time before Firefox gives back a timeout from a connection request (in seconds). - 0 will open all links as all new windows are treated by Firefox, 1 will allow no new windows and 2 is just as 0 except if Javascript tells something else

security.dialog_enable_delay - determines the delay before being able to download a plugin

accessibilty.tabfocus - determines which elements are selected when pressing the tab key, 1 is forms, 2 is other elements, 4 is links and 7 is all elements - closes downloadmanager after completion of download it true

browser.urlbar.autofill - autocompletes links entered in the url bar
middlemouse.paste - a click on the mousewheel will use the paste function, as in Linux

browser.sessionstore.max_tabs_undo - determines the amount of closed tabs you can recover

browser.sessionstore.max_windows_undo - determines the amount of closed windows you can recover

How to Create Sheet Music (Linux Mint)

Apart from writing your sheet music with pen and paper you can also use a sheetscripter. These applications allow you to drag and drop notesĀ  and all other symbols you might upon a virtual sheet and format it the way you like it. One of these applications for Linux is called MuseScore, you can find it in the standart Ubuntu repositories.

To insert notes just activate the large N panel on the top bar and drag and drop notes upon the score. To insert other symbols, open the appropriate tab and drag them onto the note or the place you need them to have.

You can also easily import .midi files to view their scores.

How to Let Your Tea Brew for the Right Time (Linux Mint)

If you would like an application that reminds you of your tea you have left brewing in the kitchen you may want to go to your Package Manager and download KTeaTime. KTeaTime is a small program running in the background for a specified period of time and popping up again after the time has run off.


You can configure the time to brew yourself and it already comes with some predefined teatime templates:

Of course you do not need to use this helpful app for tea, it can be used as a reminder for everything you need to keep track of while working.

How to change the update frequency in Microsoft security essentials

Microsoft security essentials is the free antivirus software from Microsoft for Windows 7. Unlike other antivirus tools which update their signatures every few hours, Microsoft security essentials is updating its antivirus signature database only once in 24 hours. But the update frequency can be changed in the Windows regestry and the following tutorial will show you how.

1) Open the registry editor by executing the following command on the windows console


2) Go to the key:

HKEY_LOCAL_MACHINE/SOFTWARE/Microsoft/Microsoft Antimalware/Signature Updates

Then click on "Signature Updates" > "Permissions" >"Advanced" and go to the "Owner" Tab. There click on the administrator group and click OK. Now your back in the "Permissions" Window, select the "Administrators" Group and enable the checkbox which is labeled with "Full Control".

You have changed the permoissions now so that your administrator user can edit the keys. The next step is that you doubleclick on "SignatureUpdateInterval", select "decimal" and enter the update interval. The interval is set in hours from 1 to 24.

For security reasons, you should then change the permissions back from "Administrator" group to "System" group and close the registry editor.

Microsoft security essentials will now update its signatures in the interval you set in the registry.

Please be aware that a MSE update will reset the interval back to 24 hours. As a alternative approach of updating the signatures, you can create a scheduled task which executes the command:

cd "C:\Program Files\Microsoft Security Client\Antimalware"
MpCmdRun.exe -SignatureUpdate

The commnd should be executed as "SYSTEM" user.


How to connect to an SSH-Server

To connect to a system's terminal with a static network IP and an SSH-Server installed, open a terminal and enter following command, exchanging the network IP with the one of your SSH-Server:

ssh [email protected]

Enter the target SSH-Server's root password afterwards. To exit the server's shell, enter


How to Block Web Pages (Linux Mint 11)

To block web pages on Linux Mint, there is a simple tool in your Control Center. Go to Menu > Control Center > System > Domain Blocker and you will be asked for your password. A plain window with just a few buttons will appear afterwards.

To add web pages to the blocking list, click on Add and type in the (un-)desired page. It may occur that you have to enter it two times, one with www. and one without www..

To adopt the changes restart your browser and the entered web page should no longer be available.