HTTP ERROR:601 for Airtel M2M sims

Hi all
As iam facing a problem that Airtel M2M SIMs getting network error 601 while sending data ,as gprs is getting activated and my device is assigning IP address also, so what is the problem?
can any body suggest…
As it was very clear with old airtel sim

What you are telling is that you are using the exact same system, same software and hardware, that works ok but if you just change the sim, it does not work?

Yes, Airtel postpaid M2M SIM have issues with GSM modules, they have difficultly connecting to internet. The normal SIM card connects and sends data flawlessly.

Hi, is this problem fixed ? we are also facing same issue, with same sim we can send SMS but GPRS wont get any response, it will establish connection and get local IP and connect to server but no upload or response back from server.

For M2M Sim cards, incoming has been blocked by the service provider. For this we have to whitlelist the particular URL and phone number to get response from M2M device

Hii, I am using airtel m2m simcard with sim800c and connect to cloudmqtt server. But when connecting with not secure port , it show remote closing error and when i connect with secure port(ssl port), it work fine. I am not understand how its does. please give some suggestions.