The description under ed_DialupConnectionStart (as you probably already know), is:
or the generic description:
So, could it be that this result code is something similar to the 35865 code that is received when using the standard command controlled TCP/IP stack.
In that case, it seems like your AT+CGATT=1 has failed or at least you’re not attached to the GPRS network before you try to activate your PDP context.
Possible causes could be (just a wild guess since I do not have more information):
- poor signal strength
- GPRS not enabled on your SIM
- you are using a ME with default IMEI (sometimes it registers on the network but every action is rejected by the nwk)
- faulty application code (even the best can do mistakes )