messagingtoolkit is a .NET C# messaging library that can be used to send and receive messages using any ETSI 07.05 compliant GSM modem or phone connected to the PC serial port through serial cable, infrared or bluetooth. It can also be used to send and receive MMS using MM1 protocol, and SMS using SMPP protocol.

  • As of release, it supports sending and receiving SMS through your Android devices. You will need to install the Android app APK available at Files
  • As of release, the library can be used with the Mono platform.
  • As of release, the library has been tested on Windows 10.

Do run the demo program under Administrator permission else certain features, e.g. MMS sending and receiving may not work due to system security constraints.

Some of the features of the library

  • Send SMS
  • Read incoming SMS
  • Send MMS
  • Read MMS
  • Send WAP Push message
  • Send vCalendar, vCard
  • Send Flash SMS
  • Send Picture SMS
  • Send OTA bitmap, ringtone, operator logo, or custom Smart SMS
  • Send QR Code or any other kinds of barcodes like EAN-8 or EAN-13
  • Send and receive Class 1, Class 2, Class 3 7 bit ANSI, 8 bit-ANSI, or 16-bit Unicode messages
  • Send QRCode as Picture SMS
  • Send QRCode through MMS
  • Flexibility to set content as string or byte array for binary SMS
  • Read and set various information on the phones. E.g. SMSC, battery level, network parameters
  • Read and delete messages from the phones
  • Dial, answer and hang up call
  • Detect incoming call, and automatically hang up the call
  • Multi-party call control
  • Support USSD
  • Read and write to phone book
  • Export SMS from phone/GSM modem
  • Export phone book
  • Built-in multiple gateways suport, which means you can use more than 1 GSM modems at one time, and the messages are routed and load balanced among all the gateways
  • Basic routing and load balancing (round robin) are built-in, and you can define your own routing and load balancing rules by overriding the default class
  • Ability to define group of destination numbers so that messages can be sent in bulk easily
  • Ability to detect gateway disconnection and route message to active gateway
  • Delayed message sending
  • Run-time debug mode
  • Persisted queue

There is also a demo program which shows all the essential features of the library.

You can find the assemblies for .NET Framework 3.5, 4.0 an 4.5 under the installation folder after installing the library.

Bulk Gateway is another program using the core library which you can use to send SMS and WAP Push messages in bulk.

There is also an open source SMS application server developed using the library. You can check it out here

For REST based API access, check out the open source REST API gateway here

You can see the screenshots in the WiKi.

The latest version can be downloaded here

For the older version which is written in VB.NET, you can still download it from


Manager: admin, developer

Latest news is released
New features for HTTP APIs are added in this release
Added by admin over 4 years ago

Viewer for MMS message
For any received MMS, you can use the MMS library to view the content of the file.
Added by admin over 5 years ago is released
In this release, a number of defects have been fixed, and it also has been tested with Windows 10.
Added by admin over 5 years ago is out
Release 1.8.10 is out now with support for Mono platform.
Added by admin over 6 years ago is released
With this release, you can now use your Android phone to send and receive messages.
Added by admin almost 7 years ago

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