What do I do if FrontlineSMS Desktop is not connecting to my modem device or not sending messages?

We now recommend that user's use an Android device as a gateway rather than a modem
Android phones are often cheaper and work much more stably than a modem.  They are also easier to set up and maintain.  See these articles for more information:


Getting FrontlineSMS up and running with a USB modem device can be a process of trial and error, as you have to get to know your computer and your modem. Be patient, and willing to try a few things.

If your modem fails to connect to version 2, check that you are following these steps:

  1. Make sure FrontlineSMS is not running.
  2. Insert the modem and run, or allow to run, the modem software that came bundled with it. (If none was bundled, try the manufacturer’s website.)
  3. When the modem software has detected the device and connected to the mobile network, shut it down.
  4. Now open FrontlineSMS, and give it some time to automatically connect.

If you are following these steps and the device is still not connecting, try some of the tips and tricks below:

  • Ensure that you have either removed the SIM PIN Lock from your SIM card or you remember to input the code to FrontlineSMS Version 2 as described here. Automatic connection will fail if there is a SIM PIN.
  • Ensure the software for your device has started and been fully shut down before starting FrontlineSMS by checking in the Task Manager that no processes relating to it are still running.
  • Check that no other pieces of software are running in the background that could be interfering with the device – for example, phone manager software, or a program that manages your internet dongle.
  • Very occasionally, the device manager software actually needs to be running for the modem to connect to FrontlineSMS. If the device is not recognized by FrontlineSMS, try steps 1-4 again, leaving out step 3.
  • Try restarting your computer, remembering to eject and remove the modem before initiating the restart process.  Once the computer has restarted, begin again from Step 1. of the sequence described above.
  • If you are still experiencing issues even after restarting, try uninstalling and reinstalling the device (in Windows this will be in the Device Manager under the Control Panel. In Mac OS X, check under Network Preferences and delete the relevant device from the list.
  • If you are using a Mac, you may need to check an additional setting. Open FrontlineSMS from the Apps folder, from the menu, click File, Get Info. In the General tab, select the Open in 32-bit mode checkbox.
  • Try deleting and re-adding any pre-existing connection to the modem.

If the device is recognized but not sending or receiving messages:

  • Put the SIM into a phone or another modem and send a test message using something other than FrontlineSMS (i.e. the phone’s interface or other modem software)
  • Try sending a test SMS using FrontlineSMS, but with a different SIM in the same modem. If you can, check the same SIM in a different modem, too.
  • Make sure the SIM is activated and has credit.
  • Check that no other software is running on your computer that might prevent FrontlineSMS from sending messages. If it is, check to see whether messages are being captured by it before reaching FrontlineSMS. If so, you will need to shut down that software before starting FrontlineSMS.
  • If you are using a phone, ensure that the inbox is not full.
  • Try entering the contact numbers that you are sending messages to in full international format, with + <country code>
  • Check that the SIM card isn’t storing messages locally by browsing on a phone or using modem software. By default, FrontlineSMS deletes messages from the SIM card to ensure that new incoming messages are received. This functionality may not work if FrontlineSMS is being run concurrently with another software that accesses the modem.

If you’ve tried all of these things and are still having trouble, there may be a bug or something specific to your set-up going on. Report the issue on our user support forum and we will be happy to help you.

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