Cellular Shield with SM5100B- access the network

Hi, I hope you can help me with my problem I just bought a cellular shield with SM5100B, I use this to send information to a server or an email (hotmail) with 3G network of TELCEL using a SIM CARD. My problem is that I can’t establish a communication with the internet because at the moment when I have to configured the APN it says that I have an error. The command that I’m using is this: AT+CGDCONT=1,“IP”,“internet.itelcel.com”,“148.256.254”,0,0 In this command I give the APN of TELCEL, which is the company that I’m using to be online but I also need an username and a password, and for this step the command I use is this: AT+CGPCO=0,“webgprs”,“webgprs2002”,1 But at the moment that I run this, that gives this error: +CME ERROR: 4 I just wanna now where is my problem, If you can help me I’ll be grateful, because I really don’t know if my problem is in the command or in the Network. But I also can send SMS.

I’m sorry I can’t help, but you might do better posting over in the technical side of the forums. Folks who can actually help probably won’t see your post here.