Intermittent disconnect from 3g router using usb modem dougle, one of the main reason was cause by the modem dougle itself, we have to remove the additional build in cd-rom and sd card slot so as to let the router read only the modem alone without trying to read other function that the dougle can provide.
The following step will disable the unwanted function and will not confuse the router anymore.
1) Download Putty. If the link no longer useful please google it "Putty"(Program to use AT command on modem)
2) Insert the 3g Modem to your pc
5) Click and expend "Ports (COM & LTP)" and take note of the Huawei modem (COM14). (this tell us that the modem it located under "COM14". *different pc has different number, just take note whichever number you get.
6) Now Run the Putty.exe that you previously download. Select "Series" Enter the "COM(Number that u get previously)" and hit "Open"