AT+HTTPPARA error problem

Hi all,
i am trying to post helloworld to http link.
i used the following at commands.Can anybody guide me to resolve this problem?

->AT+CPIN? \r\n
<-OK

->AT+SAPBR=3,1,\"CONTYPE\",\"GPRS\"\r\n
<-OK

->AT+SAPBR=3,1,\"APN\",\"airtelgprs.com\"\r\n
<-OK

->AT+HTTPINIT=?\r\n
<-OK

->AT+HTTPPARA=\"CID\",\"1\"\r\n
<- ERROR

after this what can i do please tell me quick

Nobody can help you here, because:
1. You have posted in the wrong forum
2. You have not specified what modem you're using or what modem chip, device etc.
3. Nobody likes to help people who write "tell me quick"!