how can i remove torjan for free in my pc?

Download Ad-ware from www.lavasoft.com and
Spybot Search and Destroy from www.safer-networking.org
Both are free and probably the best free ones available.
For best results update definitions after downloading, then start your computer in safe mode and run both programs after each other. Running both at the same time uses up too much memory and will take ages to complete.

Brian
November 2007

In addition to Peter's answer above, I would want to add some more details. While attempting to remove trojans requires experience and skill, it can be attempted to a limited success by a person with not so much of Windows skills. We are assuming here that you are using Windows 2000 or XP.

First, download a free utility called spybot search and destroy from www.safe-networking.net. Once downloaded, install it. Be sure to install all the latest updates. Now disconnect the computer from internet (Unplug the cable), and restart it into safe mode (while starting, hit F8 key repeatedly until a boot menu appears. Select Safe Mode). Once in safe mode, login as an Administrator. Open My Computer. Click Tools --> Folder Options and click View tab. Select "Show hidden files and folders" radio button. Scroll down and unckeck "Hide protected operating system files". Click Ok.

Now, drill down to "C:/Documents and Settings/User#/Local Settings/Temp" and delete all files here. Again, go to "C:/Documents and Settings/User#Local Settings/Temporary Internet Files" and delete all files where User# are all the users on your pc. Do this for all the users. If any of the users use password, remove the passwords before beginning this exercise. Next, go to "C:/Windows/Temp" and delete all files.

Once this is done, run the spybot and let it locate the problems. Once the scan is over, click button "Fix Selected Problems". If spybot can not clear all the problem, it will ask your permission to run at next restart. Say yes, and restart the system. Let spybot run.

There is no way to cure your computer 100% but this method works quite well.

If you have lost your control panel from the start menu, this means there is a virus/spyware rampant in your system. You need skilled technician to cure it. If you don't mind wiping the whole windows and installing again, please do it. Use the manufacturer's system restore method to do it. It will cure the problem 100%. Make absolutely sure that you have backed up all the information that you need on external hard drive, or another pc on the network etc. You would want to backup the items in following list, but not limited to it:
Documents, spreadsheets, presentations etc.
Pictures
Music
Videos
Emails
Address Books, Contacts etc.

Good luck.

Sanjay
October 2007

Backup your registry
Go to http://www.safer-networking.org, download and install spybot search & destroy (free).
Then search for updates (from its window)
Download and install the updates
Immunise
Search for problems
Delete them

Peter
October 2007