Hi everybody.

I have a handheld device that used to have Windows Mobile 5.0 as its OS and also it has GSM Module for using SIM card and making calls or transfering data too. Because of some reasons I had to change the OS to Windows CE 5.0. But after that I am not able to make phone calls or answer to the incoming calls anymore!!! When I insert a SIM card in it and dial its number, the device's LED starts blinking, so it seems that the GSM modem is kind of working and recognizes that there is an incoming call, but there is neither a sound to tell you that the phone is ringing nor a way to answer the call!
Would anybody kindly help me about that and give me some guidelines how to make it function correctly?! Is there any special configuration or maybe kind of driver needed for the GSM Modem to get it to work??
This is a very urgent! I need to get this device to work before this Sunday.
Appreciate your help in advance.