MMS need a standard GPRS/3G connection to be initiated over a modem. When you install your GSM modem, or connect your GSM mobile phone to the computer, be sure to install the appropriate Windows modem driver from the device manufacturer. Only modems that have a Windows modem driver defined for the modem can be used. Normally Windows will list them on device manager->Modems, Normally when you create MMS connection , the modem can be listed on modem configuration windows, refer to below screen shot:
Some multiple ports modem have not provide modem driver, You may use the “Standard 33600 bps modem" driver that is built into windows. Refer to below steps,
Finally: Switch SMSDeliverer, when creating MMS connection you may select this modem via modem list.