How to run ex_ file by converting ex_ to exe file

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Recently I came across a new type of file format which is “ex_” instead of “exe“. First I tried executing it by simply renaming it from “filename.ex_” to “filename.exe” but it did not work that way. “ex_” is actually compressed form of “exe” files and they need to be expanded. The most suitable way is to use command line. Follow the given steps:

  • Open the command prompt by going to “Start->All Programs->Accessories->Run” and then type “cmd” in Run window. Run can also be opened by pressing “Windows button + r“
  • In the command prompt go to the folder where your file “filename.ex_” is stored. For ease I would suggest you to manually copy the file into C drive. Make a new folder named say “new“
  • If you are in different directory than C then type “cd ..” and press enter. Do it a couple of time until you are :C directory.
  • Now use the command: expand filename.ex_ c:newfilename.exe
  • This command may result in following error: EXPAND.EXE Error Msg: Can’t Open Output File
  • The reason is very simple. You might not have write permission for the “filename.ex_” or for the folder “new” or for both
  • Right click on the file/folder and select properties. If the “Read Only” box is checked, de-select it.
  • Now run the previous command again. Use the expanded file in .exe format wherever you want.

Questions and Suggestions are welcomed. Enjoy :)

Sources: Microsoft

How to install Windows application (.exe) on Linux / Ubuntu with Wine

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As a new Linux user I always miss Windows for some of the applications that are not available on Linux. Booting the computer to go back to Windows just to use some specific software is a real pain. And that made me think how to install Windows programs i.e. .exe files in Linux? This task can be accomplished by the use of Wine application on Linux OS. To use this application you don’t have to be a member of a real wine club 😛

Jokes apart, Wine offers a compatibility layer that allows Linux users to run Windows application on Linux based OS.This tutorial describes the necessary steps to install a Windows application on Linux. The tutorial is based on Ubuntu but similar steps can be followed for other Linux OS as well.

  1. Install Wine application on Ubuntu. You can use Synaptic Package Manager or use this command: sudo apt-get install wine
  2. In this tutorial I am trying to install Rynga, a VoIP application. Download the .exe file of the application. Right click on it and choose properties. In the properties dialogue box go to the Permissions tab. In here check the  Allow executing the file as program box.
  3. Now go to the open with tab and select Wine Windows program loader. Close it.
  4. Now double click the .exe file and follow the usual Next-Next step as in Windows.

I wish this tutorial helped you to install Windows programs in Linux. Questions and suggestions are welcome.

P.S. Compatibility issues may be there with some applications.

How to run or install .bin files in Ubuntu (Unix)

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Being a beginner with Unix OS is a painful but interesting experience. I guess I learn almost everyday few things which might be very basic but definitely challenging for a newbie like me. Few days back I wanted to install Adobe Reader on my Ubuntu 10.10. Most of the ready to install packages for Ubntu are in .deb format which can be installed like an executable file in Windows. But this package was in .deb format. Interesting! I thought. This one is not click and install package but it requires no extra terrestrial effort for sure. Following steps should be taken:

  • Open the terminal and go in the directory where the /deb package is saved
  • Change the access rights / permission for the .deb file/package. Most easy way is to give all rights (read, write and execute) to all users by following command: chmod a+x name_of_file.bin
  • Now run the file with the following command: sudo ./name_of_file.bin

How to quickly change the Month/Year in Windows 7 calendar?

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You often use the Windows calendar for viewing the dates, don’t you? But sometimes you may also have come across the need of changing the month/year very quickly. For eg. If today is 4 Apr 2011 and you need to go to December 2004, it will take a hell of a time to reach there. Remember Windows calendar changes chronically day by day (or does it really?). Well, you might not have noticed that it can be changed in another function as well for say month by month, year by year or decade by decade.

How, you ask. Trick is very simple my friend. Open the calendar (by clicking on the time display at the bottom right corner of your desktop/taskbar). Click on the present day (see the red rectangle in the pic).

Now you can see the months in the year and can quickly change the months in that year. If you want to change the year click on the present year like this:

Here you can see the years. Similarly you can move on into decades.

The decade view.

Was it not very simple? Sometimes small things matter big times. Keep enjoying.

How to enable Secure “https” brwosing on Facebook

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Its a dirty cyberworld. And with the advancement of technology advanced are the dangers. On an unsecure wi-fi connection hacking facebook is child’s play. You might have heard of “Firesheep” add on of Firefox which enables to login in to others’ opened facebook account on the same network. Apart from that, packet sniffers can also be used to steal your password on the fly. Man in the middle attacks are also very popular in the same sense.

One of the most easy way to avert any of the above attack is to use safe browsing with https(Hypertext Transfer Protocol Secure) which is an enhanced secure version of the popular http protocol. Till now https was mainly used for secure payment transaction over internet but recently Facebook and twitter added the option of secure browsing to avoid increased compromising of their user accounts.

  • To enable this feature, go to your “Account Settings” on the top right corner.
  • In “Settings” tab look for “Account Security“
  • Click on “change“
  • Tick on the “Secure Browsing (https)“
  • Save it.

At least this will keep your facebook account safe on your network. :)

How to manipulate the routing table in Unix

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The routing table of a station can be modified or seen thanks to the route command. It may be used to add or remove entries in the table. The routing table can be displayed by “netstat -r” command (For more information on netstat command please follow: http://computerandu.wordpress.com/2011/03/03/how-to-use-netstat-a-unix-networking-command/).

1. Route command presentation:

route add|delete [-net|-host] []

command keywords signification :
add|delete : add will add an entry in the routing table , delete will remove one ;
-net|-host : -net allows to specify an entry towards a network, -host allows to specify an entry towards a host ;
destination : The destination can be a host station address or a network address followed by the subnet mask length, /20 ; The destination may also be the keyword default. In this case, the packet will be sent to the matching router if the destination network address is not specified in the routing table ;
gateway : the router address which relays the packets from one network to another;
netmask : the subnet mask of the destination network.

2. Add a path in a routing table: Use the add option, and specify in the following order : the -net option if you need to enter a network route or -host if it is a host route, the destination IP address (network or station) and the destination internet address (network or station) and the IP address of the router that will relay the traffic. For instance :
# route add -net 192.168.0 192.168.1.2
add net 192.168.0: gateway 192.168.1.2
will add a path in the routing table : to reach the network 192.168.0/24, you must go through the 192.168.1.2 router.

3. Remove an entry in the routing table: Use the delete option and specify host or network options like in the addition process. For instance :
# route delete -net 192.168.0/24
will remove the previous entry added in the routing table.

4. Delete all the routing table entries: The flush command will remove all the entries added with the add command. If you use this command remotely, it may suspend all your current communications with this router and make this station unreachable.

Remark : do not remove the loopback entry, 127.0.0.1 or localhost, which enables the application to communicate localy.

How to install and run Nessus on Ubuntu, Linux or other Unix like OS

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installation on UbuntuNessus is a great network security tool but installing it correctly can be a real pain some time even for advance user. I faced few problems and that is why I noted down all the necessary and sufficient steps. The steps below are explained for Ubuntu but I think similar steps can be used for other Unix like OS.

Step1: Download the ubuntu package from the website:http://tenable.com/products/nessus/nessus-download-agreement
and Run it.
Step2: To start nessus, type this command in super user mode: sudo /etc/init.d/nessusd start
Output of this command will result in:

$Starting Nessus : .
takshak@takshak-NB:~$ Missing plugins. Attempting a plugin update…
Your installation is missing plugins. Please register and try again.
To register, please visit http://www.nessus.org/register

Step3. Go on the given link and resgister on the home version, check ur mail get the license and use the command specified in ur mail as super user. It will register the Nessus and will also downlaod the missing plugins.

Step4. Run the nessus by using command: sudo /etc/init.d/nessusd start
Running Nessus command nasl gives an error “nasl : command not found”

(i) Try this command: whereis nessus
output will look something like: nessus: /opt/nessus/bin/nessus

(ii) Check the path see if the mentioned directory is added in the path or not by using command: echo $PATH
If the output of the command is: /usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games
then the command is not added to the path

(iii) Add the dirctory to the path by using the command: export PATH=$PATH:/opt/nessus/bin

Step5: Then start nessus by using command: sudo /etc/init.d/nessusd start

Step6: To run a nasl file use: nasl -t target_ip filename.nasl

How to use netstat : A Unix networking command

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This command displays the different data structure contents linked to the station network configuration. Here we will only talk about two ways to use netstat, but there are many other information that we can get (sockets status, routing table, multicast ).

Network interface statistics: Use the option -I (interface), and specifythe interface name to observe (em0 for instance), and the option -w 1 to display a report every second. If you do not specify this last option, netstat will only give one report in a different style. We can also specify the option -d.

Theses reports include the following information :
(fxp0) : network interface name.
packets : the received/transmitted packets with no errors ;
errs : the received/transmitted packets with errors ;
bytes : The number of received/transmitted bytes ;
colls : the collisions number ;
drops : the dropped packet numbers (with -d).

For instance :
# netstat -w 1 -I fxp0 -d will display a report of the fxp0 interface every second. We get :

Routing table display: Specify the -r option (routing table). It can be also interesting to specify the -n option and -f inet, to disable the name resolution and only list IPv4 information (use inet6 to display the IPv6 table).

Various fields signification (for a thorough explanation, use man) :
Destination : the destination network of host address ;
Gateway : the router address, the local link or the remote interface address on thelink ;
Flags :
U : Indicates route is ”up” ;
G : Route is to a gateway ;
S : Static route (manual addition) ;
H : Route is to a host and not a network ;
D : Route was created dynamically by a redirect ;
Refs : The ref field gives the current number of active uses of the route ;
Use : The use field provides a count of the number of packets sent using that route. ;
Netif : The interface entry indicates the network interface utilized for the route ;
Expire : The Expire entry is the result of FreeBSD’s unfortunate co-mingling network layer routing information with layer 2 ARP information. The only entries with ”Expire” values are actually ARP entries.

 

Sources: INPG Prof. Olivier

How to enable Google lab features in gmail?

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Google lab applications are excellent add-ons for a better e-mail experience. Most of them are still under development but that doesn’t stop you from using it. These Lab features certainly gives gmail an edge over other email giants like Yahoo and Hotmail.

To enable google lab features follow the steps:

  • Click on setting tab in the top right corner and choose “Mail settings”
  • Afterward choose “Labs” in Setting Tab
  • Now select your Google Lab feature and “Enable” it from the radio button
  • Save changes
  • Now when you click on “Settings” again you can see “Labs” option in the drop down button