//Author: Thomas 'Chaoz' Krueger
//Homepage: FXGaming.de
//Contact: Chaoz@esl.eu

#include <windows.h>
#include <ctime>

int myrnd(int);
void mykeypress(DWORD, int);
void mykeypress2(DWORD, DWORD, int);
void mymsg();
int main()
{
	Sleep(10000); // wait 10s

while(true)
{
	mykeypress2(VK_LMENU, 'I', 1);		//Tastenkombi ALT+I delay -> 1s - 5s 
	mymsg();							//Msg ausgeben
	mykeypress2(VK_LMENU, 'Q', 1);		//Tastenkombi ALT+Q delay -> 1s - 5s 
	mykeypress('B', 1);				   	//Tastenkombi ALT+I delay -> 1s - 5s 
	mykeypress(VK_SPACE, 0);			//Tastenkombi ALT+I delay -> 0s

}		//end while

	return 0;
}
int myrnd(int x)
{
	int i = 0;
	srand(time(NULL));
	i = rand()%5 +1;	// rnd 1-5
	i *= 1000;			//rnd *1000 -> 1s-5s
	i *= x;
	return i; 
}
void mykeypress(DWORD abc, int mysleep) {
		keybd_event(abc, 0xb8, KEYEVENTF_EXTENDEDKEY | 0, 0 ); 
		keybd_event(abc, 0x45, KEYEVENTF_EXTENDEDKEY | KEYEVENTF_KEYUP, 0 ); 
		Sleep(myrnd(mysleep));
}
void mykeypress(DWORD abc, DWORD xyz, int mysleep) {
		keybd_event(abc, 0xb8, KEYEVENTF_EXTENDEDKEY | 0, 0 ); 
		keybd_event(xyz, 0xb8, KEYEVENTF_EXTENDEDKEY | 0, 0 ); 
		keybd_event(abc, 0x45, KEYEVENTF_EXTENDEDKEY | KEYEVENTF_KEYUP, 0 );
		keybd_event(xyz, 0x45, KEYEVENTF_EXTENDEDKEY | KEYEVENTF_KEYUP, 0 );
		Sleep(myrnd(mysleep));
};
void mymsg(){
		char buf[] = "leave plz";
		char buf1[] = "gl n hf";
		char buf2[] = "abuser :p";

		mykeypress(VK_RETURN, 0);	//VK_RETURN

	for (int y = 0; y < 10; y++)
		{
		mykeypress(toupper(buf[y]), 0);
		}	
		mykeypress(VK_RETURN, 0);	//VK_RETURN
		if(rand()%3 < 2)
		{			
		mykeypress(VK_RETURN, 0);	//VK_RETURN
		for (int y = 0; y < 10; y++)
		{
		mykeypress(toupper(buf1[y]), 0);
		}
		if(rand()%3 < 3)
		{
		mykeypress(VK_RETURN, 0);	//VK_RETURN
			for (int y = 0; y < 10; y++)
			{
			mykeypress(toupper(buf2[y]), 0);
			}
		mykeypress(VK_RETURN, 0);	//VK_RETURN
		}
}
}

Linking...
lb1.obj : error LNK2001: unresolved external symbol "void __cdecl mykeypress2(unsigned long,unsigned long,int)" (?mykeypress2@@YAXKKH@Z)
Debug/lb1.exe : fatal error LNK1120: 1 unresolved externals
Error executing link.exe.

-danke-

void mykeypress(DWORD abc, DWORD xyz, int mysleep) {
        keybd_event(abc, 0xb8, KEYEVENTF_EXTENDEDKEY | 0, 0 );
        keybd_event(xyz, 0xb8, KEYEVENTF_EXTENDEDKEY | 0, 0 );
        keybd_event(abc, 0x45, KEYEVENTF_EXTENDEDKEY | KEYEVENTF_KEYUP, 0 );
        keybd_event(xyz, 0x45, KEYEVENTF_EXTENDEDKEY | KEYEVENTF_KEYUP, 0 );
        Sleep(myrnd(mysleep));
};

einfach folgendes

void mykeypress2(DWORD abc, DWORD xyz, int mysleep) 
{
    keybd_event(abc, 0xb8, KEYEVENTF_EXTENDEDKEY | 0, 0 );
    keybd_event(xyz, 0xb8, KEYEVENTF_EXTENDEDKEY | 0, 0 );
    keybd_event(abc, 0x45, KEYEVENTF_EXTENDEDKEY | KEYEVENTF_KEYUP, 0 );
    keybd_event(xyz, 0x45, KEYEVENTF_EXTENDEDKEY | KEYEVENTF_KEYUP, 0 );
    Sleep(myrnd(mysleep));
}

... dann hast du den Linkerfehler nicht mehr Du hast einfach nen falschen Funktionsnamen da angegeben gehabt .. bzw die 2 vergessen